I'm working on a hypothetical situation in my head here. I have a 2016 F250 for work, and obviously not having an AUX, or bluetooth in the truck while I"m driving sucks. I have an FM transmitter but the quality sucks. My question is, how would I go about installing an aftermarket headunit in this truck, while keeping the OEM radio both installed, and functioning properly? I have a steel center console that I could make a little box out of to hide the aftermarket unit in there, so that's not an issue, and I know that Metra sells OEM harness plugs, so this is what I'm thinking... Audio Guru's tell me if I'm on the right track here. I'm thinking of making a splitter harness, using the Metra connector to the factory harness, an OEM radio plug, and the plug for the aftermarket radio. I would essentially be tapping the factory harness. BUT Should I worry about back feeding into whichever head unit isn't playing music? I'm thinking of running diodes in line, but would that cause any issues? Also, the only reason I'm doing this is because I have a Kenwood head unit in a box that's collecting dust in my garage. If I do this right the mechanics at work won't notice what I've done, and I won't get into shit for modifying a company vehicle, would only cost me about 20 bucks in harness plugs too.