I mounted a Becker Europa II stereo that I pulled out of a Bavaria that I parted. This radio has a small amplifier. You can buy a DIN plug (can't remember how many pins), which fits into the same input that would have been used for the aux. tape player, and then plug your iPod / iPhone into the radio via this cord, which is very cool. And, concealing the wire in the glovebox is easy.
I didn't have the radio restored, but probably should, so I'm not sure what this may have to do with the sound quality. It could never be mistaken for a modern car with a good factory radio, but it's really not as bad as I thought it was going to be, and reminds me of the car audio I remember as a kid. I'm also convinced I could probably replace the small amp that the radio uses with something modern, and if running with an iPod, the potential for it to actually sound good is probably there. As it sits right now, it's very analog and mushy, but is stereo with a fader, so it adds to the character of the whole experience.
