The Bonneville isn't the same as the G body (Monte Carlo). It's actually the same as the GM largebody cars, like the Olds rear drive 98/88 and the Roadmaster/225/LeSabre/Park Avenue. It will be wider, and it's a perimeter style frame, which will interfere with the running boards. Most likely the engine will be either a 307 or 350 Olds, might also have a Chevy smallblock, but no larger than a 350. I agree with OldSub, an S10 frame would be a much better candidate.
