Hoggy

Hi guys! Awsome forum here! I can see there are a lot of verry respectable and knowlegable people here.
So, I live in Colorado @ 7500 ft. above sea level. I drive a gnarley old 76 ford van that has a 4x4 conversion on it. 460 C6 NP205 early Dodge Dana 60 rear end w/ 4:10 gears and low pinion Dana 44 in front w/ Chevy 1 ton calipers and rotors. Tires are 36-12.50-16.5
What I would like to do is build a donor motor to replace the old one. I want to maximise tourque more than anything. This van is usualy loaded or pulling a loaded trailer. Lotts of steep hills here.
Any sugestions for cam carb and intake would be apreciated.
I intend to start out by replacing timing gears to 0deg and am also looking for a better distributor.
This will be a low rpm engine that will not see much above 4500rpm too often at all. Last time I spun it above 4500 was pulling some guy out a ditch in the snow. at 65mph my tach reads 3200rpms. So I would like to put together a combo that will maximize torque for pulling these long mountain roads.
thanx