What size tires are you planning to run? I guess my thinking is that with 8.8" Explorer axles everywhere, and the ability of a properly built D30 to handle most reasonable tire sizes, there doesn't seem (to me) much sense in a mid-way swap with a 9" rear and ??? up front - either go full-width with 1-ton gear or stay at stock width with D30/D44 front and Ford 8.8 rear. Full-width 1/2 ton gear seems like a lot of work for little benefit.
I think there is a driver-drop D44 out of the old Wagoneers and such that is close to stock width, that would buy you quite a bit of tube strength (3/8" if memory serves) over your stock front axle setup and get you some lockouts in the process.