I had a DHE with Fulford's trigger. The gun had a broken right hammer and when I opened it up I was taken aback. It was an intricate mechanism to say the least. I posted several pictures here, and it was identified by Dave Noreen if I recall correctly. I subsequently found ads and a patent drawing. I'm not certain I could find the pictures, but a search here may help.
edit: Here's the post I made with pictures of the trigger:
https://parkerguns.org/forums/showth...ulford+trigger