Well...since you asked...
Keep in mind this is just a working prototype.
I did this a couple of years ago, from basically scratch. Sorry I don't have any pictures of me making it.
I had a headset where I didn't like the fit at all, but did actually work well. So I took the whole thing apart and mounted it inside my mask.
So it's basically a speaker and a microphone mounted inside a mask, with a 3 pin molex connector connecting it to the rest of the wires.
Of course, hardly anyone has a tool to make molex connectors, but you could easily do the same thing with a stereo mic jack...one wire is common ground, one is speaker and one is mic.
You can see the remote push to talk switch. I made it 40 inches long so I can zip tie it to a remote line. If I ever make a "finished" product, I might make the remote PTT button disconnect, so I could put a jumper in there and use a headset normally.
I used "dual wall" shrink tubing for all the important connections. Dual wall shrink has glue inside, so it sticks to the wire and molex connectors etc. With the addition of zip ties, it's not going anywhere anytime. I would recommend it for this sort of application.