I bought a radio off of amazon last week. It came in yesterday and I installed it in the Bronco. It's working great so far.

PYLE PLR22MPF AM/FM-MPX MP3 Playback with USB/SD/AUX-In

http://www.amazon.com/gp/product/B002E9GUBI

Some of the best features are:
SD card full of MP3s & remembers what song was playing when stopped
Shaft knob mounting like the stock radio, but you will have to enlarge the main hole
USB thumb drive playback - doesn't work with iPod or iPhone
Clock
AM/FM
Audio in to play from iPod or any other music/audio source

Negatives
Doesn't control iPod or iPhone
No shuffle play of MP3s. I wrote a quick app to pre-shuffle the MP3s
Clock takes a trickle of power, but still takes some power
No preset stations

I love just loading up 4 gigs of music and letting it cycle. I hate commercials and radio static so this is just what I needed.

I bought the refurbished unit for $38 delivered to my house.

That's a helluva lot of options for a radio so inexpensive. I've been reading up lately on how to mod a stock AM/FM unit with an aux-in so I can run my iPhone with Pandora. A little hard to read as a French-Canadian wrote it and his grasp of English is not that great.

How much trimming did it take to squeeze it in there?

That is a great add that you will enjoy when you are tired of hearing the rebuilt V-8.

what? :)

The dimensions of the main head is 1 3/4" by 4 1/4"

Today while driving up around Rampart Range Road, the radio started resetting on me. It would stop playing whatever MP3 it was on, then start again at the beginning of that song. I don't think it's my power connections, because tapping and wiggling them didn't reproduce the same problem. Just hitting big bumps. I'll probably have to open the unit up and see if there are any loose connections inside.

Too bad. What speakers are you using?

Ok, I added 3 more weeks of testing to this radio. I'm pretty sure it was just my hacked up wiring job that was causing the problem, not the radio itself. I crimped a new terminal plug on and haven't had a song reset in 3 weeks now.

Now I just need to figure out what speakers I want and how to mount them. These old broncos are soooooo noisy at highway speeds that speakers behind the seats wind up useless.