GM 4pin HEI run problem..starts..but won't stay running

I had this set up on my Slant 6 for a while. Ran good.
My tach lead shorted to ground from a chafed wire. Killed everything.
Once fixed the 4 pin was never the same. Changed out the module and back in business.
I worked for GM as a tech back in the time frame when those were "new". The 4 pins were hard to beat as long as they stayed cool and had grease on the backside.
Wish I had more to offer.
SN: the grease was di-electric grease used to help dissipate module heat to the heat sink in the distributor. It also kept down corrosion those big HEI caps had a tendency to collect from hot / cold cycles.
Again, very few issues with the 4 pins. The 7 pins on the other hand were not so lucky at first.
Also, dont underestimate going back to basics.... If all your wires are good then you just may have a bad module. Als,o test your reluctor on the distributor.
The pick up unit could also be not giving a good / clear signal. I dont remember the ohm reading of the 2 wires from the distributor but it should fluctuate as you spin the distributor evenly with the ohm meter hooked to it (disconnected to from the system that is) Also check your coil. You should be running an HEI coil for that module. Ohm out the primary resistance and the secondary. Might be a bad coil (getting hot?)
Joe