The camero might be too wide, usually early nova rear steers work best. use later gm disc brakes. We built a rotisserie a few years ago and put a 48 jeepster on a 78 blazer frame LOTS and LOTS of work, rework to the jeepster floor, had to move the engine back in the chassis. that means rework clutch linkage, drive shafts, body mounts gas tank bumper mounts steering probably easier to build a new frame than all the rework If you were lucky you might find an olds frame of similar years, there
is one on a neighbors farm but we have had trouble with his cows getting into our farm.