Auto Racing: 79 malibu, oldsmobile pontiac, rear axle

Question
I just bought a 79 Malibu w/ 350 engine.  I still need to figure out the tranny, but the rear axle is the standard 7.5 10 bolt.  I have the chance to get a 12 bolt from a 70's lesabre (b-body).  I have read that the 12 bolt from the chevy b-body will work with mods to the control arms and rims with a larger backspace.  I just want to make sure that their is no difference between the chevy 12 bolt b-body rear and the buick 12 bolt b-body rear before I spend the $125.

Answer
Sorry to break this to you but the chevy 12-bolt passenger rear is different from the buick,oldsmobile,pontiac and truck 12 bolt.
You will also find it hard to get gear sets for this case.
The 7.5 can be beefed up to work well on the street. Look at Auburn and T/a Performance for upgrades. When your ready for a tranny don't forget to check my site: www.lyonsperformance.com