Apparently 1968 L78 375HP Camaros couldn't be ordered with automatic transmissions or A/C. Has anyone added them, and if so, what transmission?

 

I believe that had to do with the lumpy solid lifter camshaft, you'd probably want to swap in a smoother idle modern hydraulic cam and lifter set.
You could use a stall converter for the trans but that wouldn't help with the AC pump.