I ran M/T 29.5 x 10.5 bias slicks for years. Wore out several sets of them.
I also ran 9 x 30 bias and radial slicks.
Totally stock suspension or S/S springs and hangers ??
I could not put a 28.5" slick on my 69 without rubbing the front lip - stock suspension.
You have to look at the factory tolerances to see
if one will fit and another wont... yours rubbed
by how much.. would a 1/4" cleared with no problem
because the factory was pretty sloppy back then on
the tolerances(and a 1/4" was nothing)