Your bigest issue is going from 8 on 6.5" to 5 on 5.5". Have you measure the inside hole of your 8 on 6.5" rims? Now do the same on the 5 on 5.5" rims.
(Hint make sure to get aftermarket rims, bigger hole than some stock Ford)
Ok, now check out the size of you Dana 60 hub. Now open it up and take a look and the ID, your going to have to remove a lot of metal... Think it will still hold together?
I've never seen it done. But one note of hope, the Dana 60 came in two different hub diameters... One more common than the other....