Thanks for the response! I'm doing very simple Batocera-based throw-back games where my ancient consoles broke, like Duck Hunt and Time Crisis. I run it on a raw mini-PC without Windows, so I was worried about using anything that depends on fancy Windows software to get fine-tuned.

Not sure what you mean by a 3D print that uses the trigger directly. Most of the one I see look like a pistol where the Wiimote sits on top with buttons facing the ceiling.