distributor

Pro comp sells lots of stuff (mostly made in China). Post a photo of the distributor you are talking about. Search "ready-to-run HEI distributor" here (and ebay). Many posts w/ experience if that is the distributor you refer to. I don't know how an HEI module would help if an MSD box will drive your coil.

If "stock dizzy" means an electronic one (~1972+), that is as good at driving an MSD box and probably more reliable. A points distributor is not so good. You didn't tell us the year of your car & engine.