I don't know the answers to your questions, but...
There was a guy in my 4x4 club that has a 60s era f-750 4x4 that had the manual tranny, I assume it's like you're talking about, mounted behind an automatic tranny.
I think the club has a website. www.ozarkmountain4x4club.com there maybe some pictures, or at least you can message them and ask about the truck.