A drive shaft with U-joints is not the way to go, there is more work into building a cover around it and unless you angle the relationship of the yokes at both ends you will pound the u-joints which can lead to failure.
Couplers are relitivly inexpensive and dont require too much maintenence.
Is the reason for the u-joints, because you already have a stock the 3rd member with the yoke on it? Stock Ford housings with blow the pinion carrier out of it unless its nodular iron