Will 12 bolts from first/second gen f-bodies fit in a third gen? what mods will need to be done to make them fit if they don't bolt in and what is their strength compared to a BW 9 bolt. I know 12 bolts are essential for any high power application, and the 12 bolt posis from first/second gens go for good prices, but are they worth it?

 

12 bolt is very strong rear end. you'd need to weld on all the mounting pads and clips as well as a torque arm bracket to use one in a thirdgen f body, change the end of the DS for a u joint that'll fit the 12 bolts pinion yoke, unless you can find one that'll fit the 12 bolt on one cross and the thirdgens DS on the other, plus maybe change the width of it. other than that it'll bolt right up.