Slant 6 dies when driving

this describes to the T what my 73 Duster is doing. It is really keeping me from cruising the car. I have no idea whether my rebuilt 225 had the pick up coil replaced. Is there any value in buying an old electronic ignition tester or just go ahead and start replacing things?
Also check your wiring harness to the mopar Ecu box some times they melt together, and ballast people say if the ballast is no good car won't start, but my. Brother car still started but ran like **** turns out the connection at the ballast was cracked but still made a bit of contact, do the free visual checks first then go from the cheap fixes like ballast until you get close, and good luck.