Who knows what modifications are needed to install the rear leaf springs in the front of a Samurai.
I'm planing on moving the rear leaf spring to the front as I changed the rear leafs for coil springs.

thanks

It really depends on how much work you want to do.   

I built a folding shackle setup to soak up the extra space, similar to the missing link setups in use (but not really design).  You can buy a bolt on kit for that.

You can just move your front shackle mount forward, and there are bolt on kits for that as well.

If you really want to go heavy, you can cut off your rear spring mounts, slide them back half the distance, and move your front shackle mount forward the same distance.  That way your axel doesn't move at all and you can keep the pre-existing wheelbase, just with the softer ride.  I'm not sure there is a bolt on kit for that though....

You can also run longer shackles on the front end at a bit more of an angle to give yourself more droop then just the springs allow, but if you go to far you can have more issues later.

You will need a driveshaft spacer or longer driveshaft to deal with the extra space.  A 2" spacer took care of my problem, but I plan on getting a longer shaft made up eventually.  Then I will use the old one and the spacer as a spare.

Oh, and longer brake lines.  Or just take them out of the mount like I did and use a zip tie.  Gives you that extra 2" of length. 

That's all I can think of.

Here is some info for you from another Suzuki site

RUF/CJ Swap
By Tony Filippelli   
AKA: lilbeachbum 

I’ve noticed a lot of interest lately about the RUF/CJ swap and wanted to share my recent experience with it.  I had already installed a 6� spring over kit from RRO about 6 months ago.  The kit included 4 perches, longer Ubolts, brake line extensions, rear upper/lower shock mounts, front lower shock mounts, 4 DT shocks, “over the top� steering system, two 1� driveshaft spacers.  After reading about the RUF/CJ setup on this site, I decided to give it a try.   From what I’ve heard, there are several ways to accomplish this.  The mounting point of one or both ends of the spring needs to be extended to account for the longer spring.  Some options are to relocate the shackle mounts, or to use longer fixed length shackles, or folding shackles.  Also, you can relocate the spring hanger on the fixed end of the spring.  My plan for the front was to use the Missing Link shackles and nothing else.  The rear would need CJ/ARS (alternate rear spring) plates as well as Missing Links. I began rounding up the parts I would need:

1 pair of CJ front springs
4 missing link shackles
CJ/ARS plates to bolt to the rear spring hanger
Extended slip yoke for rear

     My friend Mark had a set of CJ front springs laying around his garage, and offered to give them to me and help me out with the swap. 

     There are a few ways to do the RUF/CJ swap.  At first, I was hesitant on using the folding shackle method since I drive it regularly on the street.  But the knowledgeable people on this site convinced me that it was the best way to go, and that they would be fine for street use.  I acquired a set of 4 slightly used missing link shackles made by RRO.  I installed the shackles as soon as I got them just to see what kind of difference they made on the street before modifying any of the springs.  They provided 1� of lift and had little effect on handling or steering.  I have to say, they were made extremely well and I was very happy with them.  I got the set of four from Ebay for about $110   

    With the help of my friend Mark, we made some CJ/ARS plates using the template from this site ( http://bbs.zuwharrie.com/content/topic,1333.0.html) and some steel bought from Lowes for about $14.  I printed the drawing, made sure it was to scale, and traced it onto the steel.  You can also buy them from Trail Tough or North Coast Offroad. 

     With the advice of Brent at Trail Tough, I purchased a 1� extended slip yoke for the rear driveshaft (I later realized that I needed a 2� extended slip yoke).  Brent sells them for $65 plus a$35 core charge.  You get the $35 back when you send him your stock slip yoke.  He told me to take the 1� spacer, that I already had, off of the rear shaft and use it on the front shaft.  So I would have two 1� spacers on the front (one on the pinion end and one on the T-case end).  It took some persuasion with a hammer and a screwdriver to get the spacer off the rear.  That thing was really on there. 

     The installation went fairly smoothly.  We started with the rear.  A new hole needed to be drilled into the stock rear spring hanger in order to bolt the CJ/ARS plates to it.  I just lined up the CJ/ARS plate on the original hanger to mark the holes and drilled them out. 
For spring clearance, I used 4 bolts on each hanger instead of thru bolting it.  The plates get bolted to the outside of the stock hanger to allow the fatter CJ bushing to fit.  The CJ pack was originally a five-leaf pack, but also had an add-a-leaf in it.  We took the add-a-leaf out as well as the smallest leaf, and made it a 4-leaf pack.  The homemade plates worked great.  Combined with the Missing Links, the tire sits perfectly centered in the wheel well.  However, I was surprised at how tall it sat and was concerned that the front would not be level.  The CJs provided about 3� of lift.



On to the front.  We took the overloads out of the rear springs, and added the smallest leaf from the stock front packs.  Since I already had Missing link shackles, I did not have to modify anything else.  This ended up moving the axle about 1½� forward from the stock location, and helps prevent the tire from rubbing the back of the fenderwell.  My concerns about the height were confirmed, as the front did not sit as high as the rear.  So we decided to use the add-a-leafs that I had taken out of the CJ pack.  This seemed to do the trick and the truck sits perfectly level now.  I should mention that the truck sat about 1 inch higher in the front prior to the spring swap.
 

Results:
     All in all, I’m very happy with this setup.  I wasn’t expecting to get that much height out of it, but I’m really happy with the way it looks and rides.  I got between 3-4 inches of lift between the springs and shackles, and it rides a lot better than with the stock springs.  There is a bit more body roll than before, but I don’t mind it too much.  So far, I have not noticed any spring wrap which some people thought was going to be a problem.  However I have not taken it wheeling yet, so we’ll see.  I may have to add a traction bar if it becomes a problem.  I was worried that my shocks would now be too short and limit flex, but this was not an issue.  My brake lines were long enough as well.

     I did run into some issues though.  The front driveshaft made contact with the crossmember.  I thought the driveshaft spacer on the T-case end would have given me enough clearance, but it didn’t.  So, Mark and I modified it by cutting out the part that was making contact and welded in a piece of 1 ¾� inch tubing.
 Also, on the first test drive I noticed a terrible vibration at about 15-40 mph.  The whole truck would shake.  I figured it had something to do with the driveshaft.  After a call to Brent at Trail Tough, he advised me that since I have 5:1 T-case gears, I probably had a bent T-case mount.  He was right; the long arm was bent which I think changed the angle of the T-Case flange.  I had never felt a vibration before, but I guess the added lift caused the vibration to become more noticeable.  I installed new, stronger mounts and the vibration is pretty much gone.  Also, the 1â€? extended slip yoke turned out to be too short.  Brent at Trail Tough was very accommodating, he told me to send him the 1â€? back and he’d send me out the 2â€?.  I’ve found Trail Tough to be a great company, very knowledgeable, and always willing to help out with tech questions.  I still have a very slight vibration and I’m going to recheck the pinion angle.  Brent told me that Samurais left the factory with the T-case flange at 7 degrees and the pinion at 10 degrees.  I always thought they were supposed be equal?  I may have to adjust it using shims depending on where it’s at right now.  Also, my front ubolts were not long enough due to the added thickness of the new pack.  I bought 4 new ones from a local spring shop.  They were expensive, but I was in a pinch and paid $40 for them.  The rears were fine.  I also had to make some bump stops for the missing links to rest on.  I want to thank everyone on the board for providing me with the information I needed to do this right the first time.  A big thanks goes out to my buddy Mark Sorice for helping out.  This guy can build anything.  You can check him out at www.mayhemmotorsportsinc.com. 
Before:
   

After:

Thanks it´s more or less what I had in mind. Eventhough I have a few concerns obut the steering linkage , cause my intentions are to move the axle forward with the swap. Is there any problem with it? And mybe body roll will be a concern also since I have coil springs in the back.
thanks

I haven't had any problems with steering on mine, but it doesn't see many road miles and I have a hi-steer kit on.  There are enough people out there that I think any major concerns would have been addressed.

As for body roll, maybe someone else will speak up.  I keep a pretty stock suspension in the back just to avoid such issues. 

nc_zuk's post had a bit more in it then mine...