need rough guideline for what size TV for a fifth wheel

I'm not an expert nor did I stay in a Holiday Inn Express last night, but I have been researching the heck out of this subject trying to get us in a 5er with our 3/4 ton diesel Ford. (http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/29114791.cfm) All I can say is, if you are going to buy a truck to tow with, get the 1 ton. If I had a 350 instead of a 250 all my issues would be of no concern.