3.08 gears are not very desirable. I would think you could find a set pretty cheaply. I know a buddy had a set he was essentially trying to give away and nobody wanted them. Here's a set of brand new 3.42 on FB Marketplace for $120. Probably something similar in your area. https://www.facebook.com/marketplac...wse_serp:c855e7a4-b727-4bc1-9616-257bf46b4358
The 68 Camaro has a Chevy 8.2 10 bolt. Your 72 Skylark rear? That's an 8.5 10 bolt. They are incompatible different rears. You cannot use the guts from the Camaro to install in the Skylark rear.