My '73 3.0S is currently not running due to an increasingly wacky project that I am undertaking, so I am planning to drive my dad's '74 3.0CS up to Mt. Rainier in Washington state for my next road trip and Senior Six car rally. The guy that I bought that car from had discarded the original radio and related parts and installed a pretty cheesy CD player which finally stopped working. Before I take this trip, I'd like to make sure that there's working music and I decided to use this as an opportunity to put a proper radio back into the car for my dad.
Those cars could be ordered with a few different radios, and the Becker models are my favorite. On the non-AC cars, the radio just sits beneath the center console vents in a simple plastic panel. I found a beautiful Becker Europa Stereo on eBay and my friend Aron helped me fabricate a panel out of ABS. The result is quite nice!
One of the most interesting things about Becker radios is that they have a special auxiliary input connector on the back. I'm not sure what this was intended for originally (I've heard "traffic monitors") but it makes for a perfect interface to modern equipment, like an iPod.
For $47.96, Becker will sell you a cable that plugs into this connector and terminates into a stereo jack. Plug anything into that jack, and the radio is overridden. I took a speaker out of the car, wired up the radio, amplifier, and iPod on my work bench, and fired them up. The iPod plays through the Europa and everything sounds great!
At this point, I just need to finish up the wiring, replace a broken automatic antenna, and button the center console back up. I'm also going to add a USB "charger" circuit in the car's glove box or under the radio so that the car can charge things like iPods and mobile phones on long trips. This is simply a 5V switching regulator (with spike suppression and some filtering) that will power a USB type-A female connector.
In the mean time, I've obtained a Becker Grand Prix radio for my 3.0S, a close match to what the car originally had. Since I am converting from an AC to a non-AC center console, I'll need to also make a plastic panel and bracket for that car.