I would think so, u-joints may need to changeo No: I have swapped Chevelle rears with no issue over the years.
Bolt up, yes; fit, yes. Need to have driveshaft shortened if you still have original 8.2 Buick rear. 71 and up Buicks used 8.5 rear (monte used 8.5) driveshaft is 56" on 455 or 350 stick or 350/ 350 trans for 70 Driveshaft is 55.10 on 455/400 for 70 Driveshaft is 55.144" on 350/350 ; 350/3 stick for 71 Driveshaft is 54.241" on 455/400 for 71 Driveshaft is 54.429" on all 4 stick for 71 SO, you will need to get a 71 Driveshaft for the same style drivetrain, have one made, or shoten your stock 70 about 3/4 to 7/8 inch and rebalanced Measurements are centerline on universal joints. Source:Buick dealer service information Tech bulletin 71-I-A, Sept 25 1970
Wrong info on the monte. 1972 is a 8.2 CHEVY c-clip diff or a 12 bolt chevy c-clip diff also. NO shortening is need IF the trannies are the same 400 to 400 and 350 to 350 BUT since all your doing is the rear all you need to do is swap the u-joint. If it is a 12 bolt swap then I have a yoke that will fit the application with NO MODS to the u-joint at all. Remember the Canadian BOP cars were built with 12 bolt chevy rears some times. So I have saved some of these yokes over the years. Let me know if I can help. Steve he said he had a 1970 skylark not the 71 72. maybe you did not see that. Jim
I have 4 72 Monte Carlos and 3 have corporate 8.5" rears snd the BB car has a 12 bolt. I have owned many others and have yet to see a Monte that had an 8.2 rear!