What Dave said.

As to Number 6: For durability, almost nothing can beat a T400, and an NP205 t-case; add some Dana 60's or Ford 9 inchers, and big stout u-joints, and you should be able to run with most of the fairly large dogs. In this area, as in any other, there are other opinions, and a lot of folks will offer you alternatives that will/may work as well; but a well built T400 is almost bullet proof, and a 205 t-case is an all gear 2 speed case used in many one tons and such. They are hard to break.