Start the truck. Then with your foot on the brake put the trans in neutral(i have automatic). Now turn the key half way back, but so that the truck is still on. Within seconds all the gauges will go dead. Including the odometer. But the radio will still work.
Its because when you rotate your keys the cylinder switches one of the Acc wires off to the fuse panel meanwhile the other one remains on. Why you may ask? Its because the key cylinder is not all the way in the off position due to the truck still being in gear. You are just splitting it down the middle. This is the same as the start position, in the start position the only thing that works is the starter as this is the only wire that receives the 12 volts.
yeah a bunch of us tried that a few years ago....its ok for a little while but does something to the computer that caused problems to a few of the guys......I say if you want to save a few miles on the truck......WALK......
not to mention that it might cause excesive resistance in the switch. Resisitance causes heat, which causes smoke, which causes fire. Now who would want that? You think you 05 with 67,000 miles on it might drop in value? Try selling a 6000 pound piece of charcoal. My 2 cents.