Aww shucks, you guys are too nice with all the comments! :oops: :)
Here's a little more progress.
I was going to make a tang mounted sight but why reinvent the wheel? Not one of the older folding ladder sights but just a small peep sight. I've used the Skinner sight on my CZ 527 and like it a lot. It's pretty small and streamlined, the size is perfect for the Trapdoor except it needs a little riser.
Skinner sight and a chunk of 1/4" plate for riser. I used my cheap Chinese drill press with my cheap Chinese x-y vice with my cheap Chinese end mill bits to square it up.
https://i.imgur.com/kc2leQC.jpg
Using my cheap Chinese belt sander and cheap Chinese moto-tool and Portuguese made files it turned out ok.
https://i.imgur.com/Jdog8aX.jpg
https://i.imgur.com/I1GNeqx.jpg
https://i.imgur.com/zf3MOKe.jpg
It actually fits flusher than it appears.
Not sure if I'm going to use silver solder or epoxy to get it to stay put.