Just a question, I am thinking of installing an aftermarket head unit in my 76. I bought the car with no radio. it did have an older cassette radio in there but the previous owner took it out. Will I be able to just buy a new head unit and use existing connectors, or am I going to need to try and hunt down some hard to find wiring harness to be able to wire in a modern unit? ( and the dash has not been cut, just an fyi)