first take care of the the trim ring, i used the cig lighter ring - i used a large cone shaped grinder bit in a drill to open out the diameter cleanly and cut the most of the back off so the trim ring wouldn't interfere with the switch.
for the switch mounting, first push the button down and stick a toothpick in the side to hold it down. then lightly sand the black housing and corresponding area on the dash piece. get some industrial plastic 2-part epoxy and put a light film around the face of the switch (careful to not get any on the button)
fit the switch so the button lines up with the middle of the hole. let it dry for an hour. then mix a little more epoxy and build a bead around the perimeter of the switch. when dry pull the toothpick, test fit the trim ring - make any adjustments and epoxy it in. mine has held strong for 2 years now
for wiring ( i was lucky enough to get the factory plug and a short pigtail)
i'll try to find which 2 terminals you hook up to. hook the existing hot wire from the cigarette lighter to one terminal. splicing into the large yellow wire under the column, route a wire from under the steering column to the other terminal on the switch - use a test light to make sure you are tapping into the right wire.
button it all up and pretend you have an srt-10