Would check to make sure the drive gear on the distributor matches the cam. Pre55-235 engines ran forged cams with forged distributor gear, while the 56 and new engines run a cast cam and should use the cast gear. The distributors swap, but running the wrong distributor gear can play havoc with your cam.
The forged gears tend to be smoother on the flat sides while a cast gear has a rougher side surface but it's best to varify with parts numbers. I learned this the hard way. Hope this helps you avoid my mistake.
