The button on my XA2 has gone bad, and this may be a great idea to repair the camera. Thanks for taking the time to share this idea, and the photos showing your work. It's a clever and original mod that I had not thought of, and the my camera is not worth sending out for repair, as the repair would be more than a replacement camera, so I'll definitely consider this.
My XA2 can take some awesome pictures, and looking at the Kodachromes next to ones from the OM1n or the Nikon it's hard to tell which is which, quality wise. Sorry, Leica people, but it works great. It needs seals, and it was great until this shutter button problem came up. I can get the seals, of course. Small, handy, and "it's there when you need it." I really miss my XA2, sniffle, sniffle.