I replaced the knob on my AT shifter with an old YHM Flash Suppressor that I...came to be the owner of...before I stopped working for them.
Biggest problem with the shift knobs on our trucks is that once you take the knob off, and all the crap that goes into making a horizontal button turn into a vertical one, you're left with a steel tube and a steel rod running down the inside of it. There are no threads to screw a new knob onto. The tube has two threaded holes from where the two small screws attached the OEM knob to it, that's all.
I cut the tube down a little bit, and the rod as well. The ID of the flash suppressor was pretty close to the OD of the rod, so all I did was drill and tap some holes in the flash suppressor to pinch the steel tube.
Of course, all of that depends on what you plan on using for a knob. You'll have to disassemble your shifter and play around with it, get a feel for how it works, and compare your potential knob to the rod.
As far as the OD button, there's a connector built into the shift knob assembly that connects the button end of it to the two wires in the shift console area. I haven't gotten any further than that. I connected longer lengths of wire of a similar gauge to the wires in the console, then connected them to the leads on the OEM switch to the knob and ran them through the seam between the shifter surround trim and the gear indicator. The wires are just long enough that I can hold the button in my lap with my left hand while I steer with my right. It's inconvenient, ugly, and looks like garbage, but I haven't had time to d**k around with a new button or switch; and I cannot figure out where I would want my OD button to be anyway; so it works for me.
I'm all eyes and ears on this thread for suggestions though.
