Have you investigated the cause of the fouling? It may be just valve seals which can be rather easily replaced without removing the head. Valve seal leakage is usually indicated by oil smoke for a short time after starting, then clearing. Have you run a compression/leak-down test to check the health of the piston rings and valve sealing? If you find problems there then you are in for a lot of work you might delay with these plug anti-foulers. The problem I saw with them in an Allis-Chalmers WD-45 was that power went down due to the small hole and delay for air/fuel mix to get to the plug for ignition, then out into the cylinder.
To run civilian wires with the military cap in place, I have taken civilian spark wires and cut off the metal wire end connector projection that fits into the distributor that has the spring clips beyond the clamped portion that holds it to the wire. With a distributor cap wire boot like used on Mopar distributors in the 60's and 70's distributors on the end of the wire it can be inserted all the way down into the socket on the military distributor and the boot will fit nicely over the threaded portion where the military wire nut was attached. This way you can convert to civilian spark wires and use hotter civilian plugs to help cure the fouling problem. Not to mention that the civilian plugs are much cheaper!