I have a 5" lift kit (calmini) on my 87 samurai and would like info on the replacement of the aluminum  extension spacers that came with kit for the stock drive shafts  and put extension slip yokes. what would be best length for the front and back 1", 2" or 3"  slip yokes. also while i'm replacing u-joints which are the best out there  for angle and strength ?

Ya know Gary at petroworks can fix you up. I was there the other day looking for driveshaft parts and he wiped out all sorts of random long travel goodies. You can also have a local shop drop in a longer slip yoke into the stock shaft. Run factory Suzuki joints. By far stronger than any aftermarket. Sometimes you can pick up cheap front driveshafts and steal the joints out of them... Usually ultra low mileage as they rarely get run...

thanks  for advice ,but I still need to know which lenght slip yokes would be good for the front and reardrive shafts with 5" lift ?

If you have a SPOA (~5" lift), I would get the 1" longer slip yoke for the rear driveshaft.  

For the rear driveshaft in a SPOA application, I run a shortened front Samurai shaft; better u-joint angles, less vibes than the stock shaft + spacer.  A local machinist has done several for me and he only charges $40-$50 each.  (He didn't think that welding on the slip-yoke was a good idea as it is a forged piece.  Hence, we went with a shortened front shaft.)