So..... I have decided against mounting a screen and going with a full blown carpc as of yet. This is mainly because I recently attained a Dell Axim X51v with a 4Gb SD card.
Until I decide I want to get rid of the factory head unit I will run the following set-up:
-Dell Axim X51v w/ 4gb SD card
-ProClipUSA mounts for the golf and the Axim
-Grom connector from InDashPC
This will achieve MP3 Playback at CD quality sound and should only cost a little over 140 with shipping (because I already own both the Axim and SD card).
This setup should be more than enough for my uses until I want to take that dive and either remove the factory headunit and replace with aftermarket or run with no Headunit.
Hopefully I can get all of the missing pieces ordered by the end of this month.