All that needs to be done is 3 wires put into the stock fuel pump relay location: Power – Red (terminal 30), Fuel Pump out – Yellow (via stock fuse) and Ignition-on terminal 15 – black (to tell megasquirt when to start the car).
You simply use a regular 1/4″ terminal for the terminal 15 wire. The two fuel pump relays need 3/8″ terminals. They are larger. I found that a universal ring terminal meant for several sizes hapened to be exactly the right size. I’ve driven my Megasquirted car for two years, and they’ve never fallen out.