How does one convert the system and where do you get the components to do this?
Well, I'm the only one that drives this truck, and my switch is hidden up under the dash. Again, it's just a back-up in case my Card goes kapoot. I used a toggle switch. I personally wouldn't recommend doing that to anyone else, though. See above.
Get yourself a push-button switch, like maybe a Starter Push Button. I don't know realistically what kind of load will be going through this, I just got the beefiest switch I could find. I don't have a part number for you, but I bought a Starter Push Button Switch at O'Reilly's awhile back for about $10.
Find your Controller card up next to the steering column, it's the big black one. There will be a light blue and a dark blue wire coming out the back right next to each other, along with many other wires.
I just stripped the casing back in the middle of the wire on the Light Blue wire and soldered a jumper wire to it. Connect that to one side of your switch. If you look up onto the outside wall under your dash, you'll see a multi-pronged grounding plate. I just put a connector on the end of the other wire coming off my switch and ran it to the grounding plate.
Basically, when you ground the Light Blue wire, it activates the Glow Plug Relay under the hood on the Firewall.
As always, verify all of this first. You can take a test light or Volt/Ohm meter to see what each of the wires on your Glow Plug Relay are doing and when.
Also, if your card is still working, experiment a little. Notice the approximate outside temp and turn your key forward. See how long your "WAIT" light stays lit. You need to know about how long your GP's are warming now with the stock system so you can duplicate that manually after you convert.