Just wanted to say this thread was immensely helpful. Found a 1967 GS400 AM/FM radio after years of searching. My car originally had one and I thought it would be cool to put one back in. It was pretty dirty and I was doubtful it would work without a rebuild but it was at least all there. Took the radio apart to repair the Am/fm dial cord and clean a few things up but I didn't replace any components. Tried to bench test it but the volume was super low and nothing really happened other than a speaker thump. I just barely moved the bias adjustment pot on the bottom of the radio and it started working perfectly. You could actually see the change in amp draw from almost 3 amps down to 1 amp once I moved the adjustment pot. I dialed it in to 1.5volts after that. I am actually amazed at how good it sounds. No static, just clear sound, even with my hacked together antenna setup. I can't wait to get it back in the car. Both my front and rear speakers were blown so I picked up some new 10 ohm speakers from S&M Electro Tech. I am not looking forward to removing the dash speaker, however. https://youtube.com/shorts/n8rqe_t0U0s?feature=share
