I modified the homelink out of the sunvisor of a Lincoln Town car and installed it in the overhead console, I had 2 remotes that I was always fumbling for, 1 for the guard gate to the community I live in and 1 for the garage door, no more searching thru the console for the correct remote.
easy to install, only 2 wires which i spliced into the wires that were already there for the lamps, hardest part was cutting the hole for the buttons, as far as cost goes it was free, I work for a Lincoln dealership and this was a warrantied part out of a town car, the visor had a tear in it so we warrantied the part and I was able to get the visor which I disassembled and installed in my car.
The visor in a 2007 Lincoln MKZ. part# 7H6Z 5404105-AA is for a charcoal black interior, but I think the visor maybe a light gray in that car, it retails for $122.05,
the visor that I got out of the town car retails for $449.95, the homelink units are the same.
only 2 wires used on the unit I installed out of the town car, the unit had a green with red stripe wire which I connected to the white with blue stripe wire for power, then it was black to black for the ground. I removed the face plate from the unit and traced the outline on the console, drilled a 1/2" pilot hole in the center and used my dremel with a sanding drum to make the opening for the buttons, I went slow until the face plate fit tight in the opening, put the face plate back on the unit, stuck the unit in the console and wired it in, programed the unit to the remote and it work. you can pick one up in a junk yard pretty cheap, it doesn't matter what color because you can always paint the faceplate to match.