It depends on if this car was sold in California.
The California models came with the Buick 231 cid V6, for emissions reasons.The SBC will not bolt up, unless you swap the transmission.
Camaros sold in the other 49 states had the Chevy-made 229 cid V6, with is essentially a SBC minus 2 cylinders. So the SBC will bolt up.
You should note the 305 or 350 you get needs a pilot bushing hole drilled into the back of the crankshaft. SBC's that came with automatics do not need this hole, but the manual transmission cars do. So...uh......look for the hole
If its not there, a good machine shop can drill if for you.
BTW, don't bother with a 305. For the time and trouble involved in the swap, go for the 350. Way better.