4th gen rims on a 3rd gen?

I would like to know if I can get adaptors to use 99 Firebird rims on my 91 RS?  Someone at work gave me the rims with good tires, and I would like to use them if I can.  I know the bolt pattern is the same, but I need spacers because the offset is different on these rims.  Sorry if this has been discussed before, but searching brought up too many threads to try to sort through.  Any help will be greatly appreciated.

check ebay for wheel spacers, usually about 50 bucks a pair

Thanks for the info.  I see that there are several different thicknesses available.  Any idea what size I would need for this to work.  I don't want to have them sticking too far out.

you would need quite a bit, i looked into it a while back, i think 40mm would be fine, just because the 4th gen camaros have a negative offset on the rims, and our generation have a +-0 offset

OK, so if I did my conversion right, that would be just over 1.5 inches.  Damn, that's a lot.  How would that affect the wheel bearings?  Seems like it would put a lot of strain on them.

i shouldnt, a proper wheel spacer would just add a tiny bit of weight to the rolling mass of the wheel, but it should not affect the performane of the wheel bearings.