Engine building ideas?

[mrpbody]

I am picking up a 5.9 long block core to rebuild for a crewcab conversion I am building and I was wondering how you might build it or what modifications you would do to it since it was all tore down. Because some things are different I am basing it off of the 1991 to 93 intercooled year models.

The basics are that it is going into a 1-ton 4x4 crewcab and I will be using the nv4500 transmission. (unless you can tell me why a Getrag would be better). I pull a boat and a camp trailer (not at the same time) based on (12k lbs) and I would like to do some traveling with it but I just dread the thought of driving over mountain passes with the gas engine that’s in it now.

Drivability and reliability would be most important and with whatever combination is put together I am hoping fuel mileage will not be terrible. I guess in a nut shell, I want a tow rig with torque to pull the hills without sacrificing street-ability.

I’m trying to figure out what a good all around level would be. I know the higher the horsepower ratings the more parts start to break or the more parts you will need to go along with it to support everything else, and then it turns into a vicious circle of fixing the weakest link.

I’m not looking to break the bank or go over-board on building it and I was trying to stay with a single turbo (cost reasons) unless there was a definite reason why I should have to go with a twin turbo combination.

What kinda torque could a person expect from a 350hp or 450hp engine and is it still tame to drive on the street? At what Horse Power figure does it become too much to use as a driver/tow rig?

With your experience and some of the things you have built and know now, if you did it all over again basing it on the parameters above, how would you build it this time?