I had my own home-built mp3 player in my car as well.
I removed my center console, and rebuilt a new one, that housed a complete computer inside it. Recovered the console with vinyl, ordered an IR receiver, got the Winamp remote control software, that translated remote buttons => keystrokes. I had it where it loaded Winamp on boot, plus my playlist of all my songs.
The only thing I never did was purchase a visual interface for it. I just had a sheet of paper printed out, with all the songs, and a # to the left of them. I would type in that number, and the song would start playing.
I removed my center console, and rebuilt a new one, that housed a complete computer inside it. Recovered the console with vinyl, ordered an IR receiver, got the Winamp remote control software, that translated remote buttons => keystrokes. I had it where it loaded Winamp on boot, plus my playlist of all my songs.
The only thing I never did was purchase a visual interface for it. I just had a sheet of paper printed out, with all the songs, and a # to the left of them. I would type in that number, and the song would start playing.