Keep in mind, my front axle is 73.5" wide as it sits with 17x9 wheels and 4.5" backspace. That gives me about 6" tire outside the fender. To get a 65" wide 44, your staying 5 lug?
I am at 66 now with the spacers thats why I am thinking about the D44 still. If I could find a D44 within a 8 hour drive I would take it with out a issue.
Lock right in the front? yeah it will work fine. I have a Spartan Locker (lock right on crack) in my front 60 of my crawler, its great on and off road.
I had Dutchman Axles (www.dutchmanaxles.com) build me up a custom pair for my 60, brand new was only 295$ a pair. But I couldn't do the junk yard thing, I had shortend the housing about 9" and all the used axles I could find were tapered.
With the leaf sprung f250 44, there is no interchange for that long shaft. It is rare. If you can't find one you should be able to order one from completeoffroad.com I think the length is little over 34"