No answer on the 4-by question, but 96.4" width on the front axle width?!
I've been trying to research later model F-650/750 drive train to find a suitable replacement for my 56 C series truck. The '98 bow tie chassis currently under it (as acquired) is a non-starter.
Not to hijack, but how did you find front axle track width? I need something that's relatively within the 88" confines of my front fender spread...