I'm sure there was a post regarding the fit of a second gen about 3 months ago , I recall someone was able to use one without excessive modification. as for the Price, be careful what you buy, make sure you open the pumpking and check the wear patterns on the gears and spin the axles/gears to see if the bearings feel good. Don't ask the place to check the rear before you show up. You want to see the condition of the fluid. clear brown fluid is good, silvery thick muck bad. Decent price would be 200 but you're more likely to pay 400. for a decent rear. and that may still need new clutches for the limited posi. Remember to add the GM additive for posi rears when changing the fluid
They can be used by moving the spring perches(cutting and welding). Then the driveshaft must be shortened and rebalanced. You have to be careful about the gear ratio because higher geared carriers won't work with some lower gears. Bottom line, know what exactly what you're getting youself into before you buy.