I don't have a picture of the other side, but it is a cheap 1 1/2" x 2" adapter from harbor freight, cut a square out of the box and stuck it through and welded it in. Quick, easy, cheap, and works well.
I got this one, used, from "bus equipment ". They are in Quakertown PA, there website is bwsequipment.com. Although they do not list attachments, they do have a lot in stock, give them a call, would be a nice Saturday road trip.
You can use a SPST (single pole, single throw[simple on/off])switch for the ignition, and a SPDT (single pole, double throw [one power wire in, two wires out, one for each of the light circuits])switch for the lights.