I have done it both ways. If i have a reason to sit the tranny out of my way then i do so. FYI flywheel inspection removal/reinstall as well as pilot bearing/bushing replacement does require a good bit of room so the tranny will prolly be in the way if under the truck. To each his own way and reason for doing it his way.
Yo Elmo,
I agree! It is similar to replacing oil pan and /or gasket..jack eng up while loosening a few parts vs pulling engine
either way, fragile vacuum hoses and device, exh pipes, wiring harnesses/connector feel the strain.
I found out before I was 6 yo when dad and uncles would go to local yard to swap LaSalle engines into Caddies.. many parts would snap as they jacked eng up.
btw, for posterity, in at least 92-96 Bronco, F Series and almost all other models;
"...The vacuum hoses used in the passenger compartment control circuit are constructed from PVC plastic material.
The vacuum hoses used in the engine compartment are constructed of Hytrel. Because of the materials used, the vacuum hoses should never be pinched off during diagnosis to locate a leak. Use Rotunda Vacuum Tester 014-R1054 or equivalent to locate vacuum leaks. A wood golf tee can be used as a plug when it is necessary to plug one end of a vacuum hose for leak test purposes..." from F-150, F-250, F-350, F-Super Duty and Bronco, F-Super Duty Motorhome Chassis Workshop Manual