I think "adjustable" means "by replacing our OEM fixed bushings with something else."
From my very limited experience with E450's (2002 and 2012 front axles), Ford ships chassis with offset bushings, at least in the cases I've looked at. On the 2002, they MAY have been added by original owner, but with their approach to maintenance, I doubt it. I KNOW the 2012 came with offsets. But as I said, they are FIXED offset. To adjust further requires either adjustable bushings like Ingalls 594 or the comparable one from Specialty --OR-- a different fixed bushing.
In Harvard's case, it seem the coach builder chose to install Ingalls adjustable bushings.
