Looks like that button should do more than open the garage.. Like it should launch a missile or something. 007, Prius style!
Sorry PriusCamper, I don't I actually installed this over a year ago just been too lazy to post! Something this doesn't show is that I have a power regulator under that plastic cover to step the voltage down to 9V for my garage door opener circuit.
For the converter try Googling: 12v to 9v converter For the switch Google: push button momentary switch There are a lot of choices.