The Four Degree can be set to Zero. The Two Degree apparently cannot, since those instructions start with removing existing bushings, installing a Zero Degree (from Ingalls, or Specialty, etc.) then checking Alignment on the Rack. Use that info to dial the Two Degree in. For Four Degree, they say to set it to Zero/Zero and to the same "alignment sweep." Makes me wonder if Two Degrees and Four Degrees are determined from the same benchmark/Zero...
Anyhow, our new axle came with offset bushings. That suggests Ford's "Generic Alignment" doesn't use Zero Degree Bushings.
There's a lot to be done on other fronts before I can take on Springs, Bushings, and Alignment.
Harvard, when you set Toe with a Tape Measure, what "difference" are you looking for? I tried to get ours about 3/8" less across the Fronts of the Tire Treads, than the Rear.
