Here's the thread I posted on SF back in 2007.
Add MP3 to virtually any radio with changer capability.
I just got this neat device. It is the M.Costa MC-9088 mp3 music changer.
What this thing does is simulates any cd changer i/o language, so you can use it in place of a regular cd changer. Is has an SD slot and aux in.
To toggle between mp3/memory card and the AUX input, you just hit the "repeat" button. Very convenient.
I got it for my toyota camry, but upon reading the manual, you can also emulate:
Alpine M-Bus and Ai-net
Honda 2.0, 3.0, 2.4 and 2.3 series radios
Toyota (small and large)
VW 8 and 12 pin
You can pick up a 2001 Camry radio for around $40, then get this mp3 changer for a nice stock looking setup.
only $79 from that place I can't mention!
It says you can use up to 32gb hard disk:
CD changer interface connection. NOT FM transmitter, NO tone loss, NO noise and NO interfere.
Add multyple CDs, thousands of TRACKs on radio. MP3 Control is exactly same as CD changer.
Disk folders is mapped to CDs, files is mapped to tracks. Organize your music more easily.
99 songs each folder can hold, 98 folders(CDs).
High quality MP3 player build inside. Support up to 320Kbps MP3 encode rate. Nice voice present.
Radio button (and steering wheel) can control the MP3: Mode/Disk/Track/Volume/On-Off...
Repeat/Random/Scan play mode can be done. Display accurate Disk/Track/Time message.
Standard USB 2.0 interface and SD Card. Can use most kind of USB memory stick
FAT/FAT32 partition on USB disk. Up to 32G byte songs can be listed and played.
Car noise restrain circuit build inside, restrain car noise and interfere perfectly.
Can remerber the exact position of song. Continue playing when radio power on next time.
All power supply by Audiolink. Not cigarette plug occupied. No wire outside.
1/8''(3.5mm) Line in jack is available for other audio resource connection.
Keep the original internal CD/CD-changer usable.
OK, just installed and it works great! the functions are a bit slugish, but otherwise the sound is indistinguishable from a regular CD.
I was told any size thumb drive would work, and any usb hard disk up to 32gb would also work.
So far, I'm very happy with this unit. I'm going to get one for my old school Alpine 1310 as well... or take the alpine out and get a toyota radio for a stock look.
As far as folders, you can have up to 98, and 9,000 songs. It just seems to cycle 1 - 9 discs, but keeps going alphabetically through all of the folders.
Toyota radio model #16814
MP3 changer installed in the center console.