Designed to drive HEI module plate...

That looks nice, home made?... Tired of 150-260 a box, every decade, or so.... The thought, was to have : the car breaks down, parts are available.... Much appreciated...
That's a stock bracket I pulled at a junkyard and mounted to the fender with a piece of angle plate. See here, same one is in this thread:
Slant Six Forum, :: View topic - HEI Electronic Ignition Retrofit How-To