Well, I dun finally did it!
I got a switch, backplate, and wiring harness from the junk yard. I got out my Dremel tool, and carved off the blank on the original backplate, so that it only contains the top two switches, then I carved off the bottom hole on the junk yard black so it only contains the bottom switch. So there are now two blanks in where there used to be one. It seems solid enough, and it doesn't move around or rattle. The new switch is wired to the trucks dash lighting, and the trucks fuel pump via a relay.
The best part is that it looks OEM and most thieves(who don't read this forum anyways!) wouldn't think that the airbag switch is the kill switch when the truck doesn't start.