According to the Tech section "7.5 inch rear end dropped and replaced with a new 7.625 (7 5/8) inch rear end for all Camaros.

Where can I find gears for this rear? How do I tell it apart from a 7.5 (my buddy has an '83 rear for sale)

 

There is no difference in those gears. I have no idea where people get the idea that there are 2 diameters of these things. If you look in the books, the gears are listed for 78-2000 cars & trucks, including A, B, F, & G bodies, and S trucks.

Try www.drivetraindirect.com or www.drivetrainspecialists.com or IRS at www.racenet.net or www.differentials.com

 

After I posted that I found this @ Summit: GM: 10-bolt, 7 1/2 in., 7.625 in., 4.10 ratio, 2 series carrier, ring and pinion