I've been looking for this same conversion for my '79. Did you have to modify the brackets /backing plates at all? Everything I have found has the "Square" bolt pattern, where my rear has normal holes on top side of the axle housing and closer very small holes on the bottom. Also, what type of e-brake setup was on the Camaro rear originally?
Try a speed shop for line lock, as it's standard drag equipment.
There was also someforeign car (Subaru?) that had a "hill holder" for standard trans cars -- held the brakes for you while you had other feet oddupied with gas and clutch -- for those who hadn't learned heel&toe. ;-)