No, what they're saying is that it's lifted now. Or something else is whacky.
Look underneath and you'll see a link/bar between the frame on the driver's side (near the steering box) that runs down to the passenger side of the axle. This is a Panhard Bar, or the "trackbar" as Ford and Dodge call them.
As the suspension cycles your axle is going to move sideways as this bar travels in an arc.
As the suspension extends (body going up) the axle shifts to the driver's side.
As the suspension compresses (body going down) the axle shifts to the passenger side.
So lifting it more will shift your axle more to the driver's side than it is now.
That's why an adjustable bar was mentioned. But first determine what height it's sitting at now so we can help figure out why it's shifted.
If you measure between the bottom of the frame rail and the top of the axle tube, the front should be approx. 7" and the rear would be approx. 6" or so.
Give or take half an inch.
If it's higher than that, you have a lift. Or a very light Bronco!;D
If as you think, it's not lifted at all, then maybe check the tires against the frame rather than the body. These bodies are not exactly a perfectly executed thing like modern cars are. They were lowly utility vehicles, before the "sport" was added and built on the truck line. And then 43 years of Previous Owners can have their effect as well.
Is there a body lift installed by any chance? Maybe the body has shifted sideways?
To measure for body lift, a stock rubber insulator between the frame and the body is 3/4" tall when new. Old ones are almost always sagged down some. Anything taller than 3/4" is a body lift of some sort or another.
Good luck.
Paul