So I scored a set of 5 235/75-15 wintercat snow tires on bronco rims. Unfortunately the center bore is to small in diameter. Fortunately I lready had a spare set of 8" rims that fit my tracker.
#1 Any gueses what I should expect to pay to have a machine shop increase the center bore diameter?   Any suggestions in either Portland or Salem OR?
#2 The metal is much thicker on these rims than any I have seen before. I'm guesing that would give them a heavier load rating for a f150? Is thicker / heavier better for mild wheelng? or is a lighter more typical steel rim a better way to go?

I'm debating whether I should sell the rims or put the $$ into them ans keep them for my next set of tires

I did a set of aluminium factory Ford rims on a Bridgeport Mill with the tires on them. Mill the center bore out to 4.25.... My shop charges $50.00 an hour and it will take them an hour to do all 4. If you can find a friend who works in a machine shop the hourly rate gets much better.....  

Does anyone have any opinions if the thicker / heavier rims are better or worse for a sidekick. I know in the miata world lighter is almost always better for performance.

I think they are way overkill for the tire size you are running.  Aluminum rims are the way to go.

It depends on what you are looking to do.  Aluminum is lighter and should give you a bit more power, but if your wheeling and in low range it won't make all that much of a difference.  And it's easier to pound a dent out of a metal rim.

Thats what I do most and pounding a dent out of a rim is rarely a concern.  The reduced unsprung weight is well worth the very small risk in my opinion, especially when cruising down a gravel road full of washboards.
 

Aluminium rims take a pretty good beating. Drone's point is a dead on if you wheel in an area that is rocky or you might bounce it really hard.

If your a drivin down the road / me & my buddies wanna play in the mud or run down thru the creek kinda guy these will work for you.

I love aluminium rims because of the durablity, light weight, and easy maintenance. I have them on my Samurai because I put 9.5 x 34 x 15 TSL's on it and wanted to keep the weight down as much as possible. Anything to make life easier on the drivetrain / motor is a good deal both on and off the road.

Here is a pic of the aluminium factory Ford Outlaw II rims that I milled down and have the same size tires (235 x 15). These are on my Vitara.....

I think that settles it ... anyone want to trade  / buy a set of steel ford bronco rims? ... will post up in classifieds when I get pics