@mjrice I have exactly the same question. I'm in the process of rebuilding a very high mileage Wilson TS I acquired as my first printer a few months ago on the way to building a 300 sized DBot.
I got a new Pica board and some MakerBot style endstops on PCBs with 3 wires. These ones specifically.
I notice the Pica has holes but no pins for Vcc. Can I simply solder in the pins? Do I gain anything more than just an LED indicator? Will they even work without it?
Thanks in advance.