I built this super simple touch plate with parts I had around the shop. I used a 1-1/4" hole saw to cut a plug with a hole in the center from a scrap of 1/2" Lexan. I used a paddle bit to cut a pocket on the top, and drilled an 1/8" hole from the edge to the center hole. The metal plate is a Gameworks token, ground flat and polished a bit. I soldered the center conductor of an old guitar cable to the bottom of the token and dropped it into the hole with a drop of epoxy, pulling the slack back through the hole. A cut off alligator clip jumper soldered to the ground shield and sheathed in heat shrink finished off the business end. A 5 pin din which fits into the home/limit jacks I use on my motor controller completed the project.
Nicely done