I'm glad you posted this,because the switch on my truck is missing and has been jerry rigged with another toggle switch,and the gauge just pegs over full and flicking the switch does nothing--I'm in the process of converting back to a single tank and your wiring dilema will help me figure mine out--I have a clymer book with a diagram,but its so small its very hard to read. /forums/images/graemlins/angryfire.gifHope to make it work--or this will be the third GM truck I've had with no gas gauge--now THATS annoying!. /forums/images/graemlins/grin.gif