The Ready-To-Run HEI distributor by Ningbo is easiest and only $45 (ebay, Skip White Performance and others). You also need an e-core coil, which they also sell, or grab one from a Mopar Magnum V-8 engine. For less cost, you can use the Mopar e-distributor to trigger a GM 8-pin HEI module. Many posts. Grab from a 1985-95 junkyard V-8 truck and also grab its coil and cable between the two. I definitely wouldn't fool with the Mopar ECU box since it needs ballast resistors which you would have to kludge into your wiring and is less powerful, plus many replacement ECU's are faulty. Below is the 8-pin HEI on my 1964 slant engine.
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