I have an aftermarket mechanical gauge, along with an oil pressure gauge, that I want to install in my vehicle to show actual pressures/temperatures. My main issue is the water temp gauge. Since I can't disconnect or cut the tubing from the sensor or the gauge, what is the best solution to get it into the driver compartment? The instructions say to drill a 3/4" hole in the firewall to pass the sensor through to the engine compartment, but I really don't want to drill that big of a hole. Suggestions?