Okay, I think this has been hit on before, but I have an aftermarket oil pressure gauge that I want to hook up. The sender unit is 1/8" 27 tp, and of course the location that the oil pressure sender should go is a metric thread. I've read that I should tee it off and have both connected, but that sounds like its more trouble then its worth. I've found the adapters to attached the aftermarket sender, and would like to know how to fool the idiot light into thinking it has good pressure, as the factory sender is just a switch. I can't see the purpose of having both an idiot light and a gauge, the gauge provides far more information, and I think I'm just as likely to notice it as the idiot light.