weird cutting out problem

Sounds like you are losing ignition power sporadically. Carry some starter fluid to rule out a fuel problem. To catch it in the act, run long wires to a multimeter in the cab to monitor coil+ to engine ground as you drive. You might be losing IGN supply thru the ignition key and bulkhead connector (common problem).

Another possibility is a poor ground on the ignition module. Are you relying on a rusty sheet metal screw (like most readers do), despite the constant suggestions to run a dedicated ground. This is true whether the old Mopar box or a GM HEI module. Even an MSD box requires a good ground to the engine block. Always carry a spare ignition module in the trunk.