I gotta say that the cheap and easy way is not the direction you're heading with your build already, which would be the direction you would be heading it towards if you put an ls motor in, just get a built aluminum or titanium block based off the boss 6.2l, bored and stroked to 7.0l, it is a better design than the ls motors, just no one has taken it even near it's potential yet, remove the 4x4 system, but I'm not going to say removing the bed is a good idea, it's a pickup truck, people add weight to the rear end of drag trucks for a reason, get it weighed with scales at each wheel and remove and add stuff until you get a balanced weight distribution both front to rear and side to side, doing the weighing with you in the driver seat or something that could properly represent you would be the best way to do it