I had this version running on my mogul and for sh!ts and giggles I updated to the new XT interface (v5.00.10w) It is Garmins new version where you can download cars to replace the directional arrow. Other interface changes as well.
All I did was download the XT updated version...
http://www8.garmin.com/support/colle...t=010-11034-00
Then the updated support files...
http://www8.garmin.com/support/downl...ls.jsp?id=3493
Then the updated BaseMap...
http://www8.garmin.com/support/downl...ls.jsp?id=3493
Follwed the instructions with this threads version and whammo...All new fully working Mobile XT