First it sounds like a bad HEP, I know you said you replaced it was it a Mopar one or aftermarket? I have seen new aftermarkets fail.

My next thought would be your aftermarket coil. I know i have read on either Gus's or Gary's site (if i recall right) that the aftermarket ,like MSD, coils have the wrong internal resistance which can cause problems for some but others have no problems. I know some will buy a junkyard Mopar coil before aftermarket.

Next I would look at the Fuel pump, with the aftermarket and the bad wiring, i wonder if it handles a load, My dad had a problem and was told to but a pressure gauge on it and then start to pinch off the return line, you should see the pressure hit 100 psi and hold at least for a bit, and in his bad one it would just spike and then die off as it couldn't really handle the load. I wonder if bumps in the road are cutting out the fuel pump with the bad wire.

Also look for any frayed or previously repaired wires (look for electrical tape repairs) for example my van kept on spiking the voltage to 18v and holding for a bit, and it would always do it while turning left, but not right. Weird but i found that the battery signal wire was taped over and underneath only 2 strands were left, so after repairing that the problem was fixed!

As stated before there can be many problems. here are some of my ideas i hope they help.

Also are there any CODES?