454 4x4 k10 cam and heads?

[mud slut 350]

So I have not done much with engine work. I know quite a bit about suspension but not a whole lot about building an engine. When i get home from the desert i wanna find a 454 short block and do something similar to this link,


http://www.superchevy.com/technical/...d/viewall.html

I have a few questions. This one was built for a car so it gets it most power even w/o NOS which i will not be using at almost 6000 rpms. Iwant to build one that gets its power lower so i have more low end kick for crawling but still engough high end to carry it through mud with 44's and 4-10 gears. I dont know what year block is best to get, and what heads and cam to get, or if i should go with aluminium heads or iron. Kind of worried if i get aluminium they will crack if they get wet is this true or no? Ive tried looking but every site that has an artical about rebuilding a 454 is for a street car and at crazy rpms. I need low end power and torque for my truck. Any help or suggestions would be great! thank you!