Guys,
I often do not use a trigger plate. I use just a square "nut" to hold the end of the tang screw. The trigger I make uses a blade of full thickness of the trigger, like 1/4 inch, rather than the thin blade of around 1/16 inch. This makes the trigger a whole lot easier to make, just cut the thing out of 1/4 inch stock, smooth the edges, done. it is really a lot easier to inlet a 1/4 blade into the wood and get a good fit than the thin one. When drilling the pivot pin hole, just press the trigger blade tight against the forward edge of the inlet cut which will give you the forward trigger stop function. Also, the pivot pin passing through the 1/4 inch thick blade is a lot less apt to wriggle/wobble than a thin blade.
Here is a "cheapie" pistol I made as a donation to a raffle with the trigger done this way. Really, it took a lot less than an hour to make, inlet, install, and tune the trigger. On nicer guns, I do use the trigger plate as is most common.
Jim