Some years ago I got talked into rehabbing a Courier Royale 23-channel base. Had that fat socket on the front. We discovered that the "front load" style 4-pin mike socket would slide right down into the outer body of the plug. The black plastic insulator is held in place with a single flat-head screw, and just gets removed to make room for the new socket.
The more-familiar "back load" style of the 4-pin 'Cobra' style socket has the nut on the outside. This one loads from the front, and has a round flange on the outside, with the nut on the inside of the mount surface.
Had some pics on ImageShack, but they have disappeared. I'll see if they survived the last 15 or so years at the shop and post what I can find later. Simply pressing the new 4-pin socket into the old housing is not the whole job. We scrubbed the metal surfaces and filled in JB-Weld on the rear of the thing, putting a sleeve around the four pins to keep the schmoo off of them. I don't know how often he uses the radios we used this trick to convert, but the modified mike socket hasn't failed in any of them yet.
Just made more sense that making an adapter cable.
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