i know theres atlease one on here that did that. but his was diesel and he doesnt get on here anymore due to the lack of attention he was getting. but anyway, its unsafe cause you would have to mount the tube or line under the tank and frame rail which depending on your truck height might have a chance of snagging something and ripping it off.
best bet is to fix it right. i wouldnt put a DPDT cause you would have to rig up the wiring. the switches are somewhere around 15 and you can just put it right back into the hole where youre old one came from and you dont leave a hole in the dash