I'm sure you know you can buy just the 4 wire module inside the HEI and remote mount it / hide it about anywhere, it's about the size of a business card and about 5/16" thick.

Accel used to make an aftermarket one, it makes for a really decent perfoming low buck HEI and it's super easy to wire.

it's great for older mopars who want to look oem and not mount a chrome/orange box in the engine compartment.