HEI first started in '74 or '75 if I remember right. You want one from a Chevrolet V-8 from before the computer days, and if I remember correctly before 1980 is about right.
You might want to price a new one. I bought one at a local parts store once because I didn't want to mess with used. This was less than five years ago and it was something they had in stock. I think I asked for one for a '75 Chevy pickup because the '75 Chevy pickup I once owned had one.
Stuart is right, you don't need the resistor once you swap to HEI.
I'd still like to come over and trouble shoot this thing with you, but it will be after Christmas now before my schedule allows it.
