I'm more familiar with the 145, but I would think it had similar hookups. I got tired of fiddling with the pressure plates, so I went to using an insulated rail which basically works as completing the "common" side of the circuit. I also ran the power feed to a separate output to be able to adjust the voltage so the guy doesn't look like he's flying out the door when activated. It actually makes wiring different accessories much easier when I started using the track as the "common". As long as you sequence them (you have to figure out which way to plug them in) you can use multiple transformers all with the same common.
Here's a previous thread with some basic diagrams.
To answer the question about the guy being so big, I recall reading somewhere that it was developed prewar to be used with both standard gauge and O gauge, and it just carried over into Postwar with the 145. Similar reasoning behing large crossing gates and signals, etc.
Edit: Looking online I see a pic of only two hookup posts on the 45N. That makes it even easier as the extra wire on the 145 is just to keep the light on constantly.