Since the F-150 and F-250 used the Dana 44 front axle can I just use a set of F-250 spindles, rotors, calipers and hubs to make it an 8 lug front?

 

You sure can. That is the exact parts I used to convert my F250 to 4wd. Some will tell you that you need the knuckles out. You only need the spindles out. Ted

 

ford Dana 44HD 8lug parts will work
Chevy Dana 44 8lug parts will work
Ford Dana 50 8lug parts will NOT work.

 

Add to that. Ford drum setups have 5 bolt holes in the knuckles / spindles and disk setups have 6 holes so swapping from drum to disk setups require replacing knuckles and all. Can't have drum knuckles and disk spindles ect.
I just did the 8 lug conversion. Completely bolt-on and go.