Sorry iskipowder, I have no clue what that means? Super Duty, is that a company? What is the part number. What is the max vehicle weight? What is the horsepower max value? What is the max torque value? Do you know whether it is suitable for your truck under the WORST conditions?
Do you know what a "tractor fund" is? Have you ever exploded a T-Case in your rig and needed to walk then hitchhike to go find a truck or tractor big enough to rescue you(>100 miles away and a WAD of Cash)?
Oh and "some proprietary parts" scares me the most! If I were you. I'd have an exact spare t-case on a pallet, with a Buddy I can to call... So that he can ship it to me!