brake lights in an old delivery truck

A bunch of people at work are pulling funds to create a Tailgating truck. They bought a 1977 Delivery truck, not sure what kind. We removed the rear bumper which had the brake lights in it that didn't work anyway. I'm putting in new wiring and lights. I bought a trailer wiring kit from Wal-Mart to get my lights and wiring, but now I'm to the point that I'm not sure how to do this. I don't want to try to figure out what's already on the truck because it's a big mess as it's been redone several times. I want to put in a new switch on the brake pedal and everything. What do I need to accomplish fully wiring the brake lights and signal lights? How do I wire it up? I've done remote starts in the past, so I'm not new to wiring that aspect of the vehicle at least, this is just new to me. Thanks!

The first thing you need to do is figure out if your going to run a two or three bulb tail light. Two bulb, one dual filament (one filament handles turn and brake and the other does running lights) and a single for the back up lights. A three bulb would be easier, one bulb handles the brake, one bulb handles turn (on one filament) and running (on the other filament) and a back up. I just drew this out quickly. I believe this is the way it works.

I forgot to put in a switch for the running lights, just apply 12v.