HEI Distributor Recommendation for ZZ3 Crate?

[ZZ3ElCamino]

I am using a rebuilt Mallory HEI (8 years old), and I seem to be having problems with the coil or some other part of the ignition system. I don't seem to be getting all 8 cylinders firing, and the plugs were fouled worse than I have ever seen before. The car will idle just fine, but when the car is throttled up the car spits and sputters. At first it was acting like a carburetor problem, so I replaced the old Edelbrock performer with a new Holley and this did not fix the problem. I also put new plugs in it and this also didn't help. I currently have the distributor at a local shop and they are putting it on their distributor machine to test it.