First and foremost, in 2004.5 the Common-Rail Cummins 5.9L was rated at 325hp and 600lb-ft. Latter 2005 the torque was increased to 610lb-ft.
Secondly, You are looking in all the wrong places for a good 6BTA Cummins. You need to slow down and keep an eye out for wrecked or otherwise damaged vehicles that had either 4BT or 6BT in them. You're not going to get a half-way decent deal trying to buy a running/driving truck just for the engine. You obviously don't know as much about diesels as you claim if you are dismissing the 4bt as being unable to do what you ask of it. It's no powerhouse, but I'd put it up against a gooseneck trailer any day of the week...
