Your gonna be pulling your diesel right? Gas motors you have to deal w/ vac. checks sometimes, yes hitch height is just like tractor pullin. Do you wanna pull in stock or mod? In mod around here you can have your suspension solid, for stock I think you have to have 2 inches of travel on the rear (no blockin it up) in the stock there is no putting weights in the front, some ppl try to sneak em in the engine compartment and then they are DQ'd, but last year is when they really started crackin down around here on chips and everything, they check you and can tell by your smoke, if your running a chip they actually were checkin it's setting right b4 you hooked (you were aloowed up to 60HP, other then that they didn't care about exhaust, but they will sometimes measure your turbo (usually only the winners)