Hi,
First of all, nice work on the carputer. This is the first time i post here but have been browsing and getting info from this site. Now, I think i should contribute a few. Browse to this site; http://www.ngine.de/index.jsp?pageid=4176. It got all info of how to install XP directly into the USB drive, either pen drive or hard disk. I tried it for 2 month now and it seem stable. I can use it to install driver and everything you normally use on XP including Garmin and bluetooth.