I would find a engine harness first that will get rid of a lot of it, you want a 8 cyl harness for the engine, don't think the dash makes a difference except maybe year, not positive on that except the seat belt interface. You might just have electrical issues? Mopar electronic distributors are very reliable, the control boxes do crap out but they are a easy change and usually just die. You have to watch with the one wire that it has the right curve for your engine or it can be a dog.
