The key is still required. The way mine is setup I can use the key to start the truck just like normal. Or flip my "valet" switch and when I turn the key to run the radio and everything turns on but if you try to start the truck nothing happens. It is more or less a novelty/safety feature. You have to have the key in the ignition and in the on position for the push button to work.

It wasnt that hard as long as you can do simple wiring and a little fabricating. Let me see if I can find the right up on it...

Here is the write up I did. If you have any questions just ask. https://www.f150forum.com/f4/cig-lighter-start-28976/

Hey man, was wondering if you ever ended up sending your switches to xpertise and how they turned out?

hey, noticed in one of your posts that your in houston. my parents and i are just moving there ourselves and i was wondering if there are any good shops and garages down there? any to stay away from? i am from boston so itll be alot different down there and many much nicer truck as well im sure. Screw's all the way!
thanks- chris