Hot wire in park only?

[BPlatt]

New to the site and in need of help. I'm looking for a wire that's hot in park only for my 97 sierra 5.7L 4L60e. The reason for the wire is that I'm building a push to start unit from scratch and this is the only wire I'm lacking. I need it so that no one reaches over and hits the button out of spite and turns my truck off while driving (not a fun experience). Any help would be greatly appreciated.

 

[low4x4]

is this wire for the start function.....what if your in park and someone hits the button....do a security double switch ....toggle switch on and push button start

 

[BPlatt]

It's a Single push button to control on, start, and off. I didn't want the toggle switch like most do then the push switch. I know that the park safety switch is built into the start farther along the circuit. If i'm in park and someone hits the button then I don't care, I just want to prevent comedians from hitting the button while not in park or I to hit it by accident shutting off the truck while driving.