LOL... I was getting real excited about learning about your new tow vehicle, but you really mean a television!
There have been many posts for replacing the glass tubes in their rigs in favor of larger, lighter LCD or Plasma screens. There have been posts for persons who have mounted new screens on the outside framing of the existing cabinetry, inside the framing, inside the cabinetry and using a slide mount or a scissors mount.
I hope other members, will just post the links to these topics as responses to your post and save you some time. I'll go search for some now.