I bought a 69 Camaro recently. The problem is that the guy I bought it from replaced out a 4.11 posi rear end with a 308 open differential to up the mileage. He did increase the mileage, and I am happy about that but there is no posi-unit installed.

Of course, I'd love to put in a 12 bolt, but $$ preclude me from doing this. I did a bit of reading online, and will keep the 10 bolt 8.2" that I have. In fact, I think that I will keep the 308 gears ratio to, since this helps on gas. But, I really would like to install a pos-unit.

Here is the question: Not knowing anything at all about trans-axcels, can a posi-unit be integrated with the existing parts, or when installing a posi-unit, are there other componants/parts that have to be changed our as well?

Also, what should I expect to pay to have someone to do the job? Any recommendation on what brands I should consider?

The car has a 454 (545 hp) and a TH350

Thanks for any advice or thoughts