Sin City

i've been lurking for a short time and came across a post that got me thinking so i figured i had better intro myself before i start firing away with questions. i'm looking at the idea of an HDT for a tow vehicle for my boat (WAY overkill) and will have a few questions for you guys along the way. i'm not going to be looking for a rig that i can "full time" in, more of something that may be an over-nighter.......on to my questions and thanx in advance for the help!