To start with: Factory Hardtop July 1974 with rear hatch.
Donor top: 1981 Bj42 (??) Canadian model.
The header bars at the top of the windshield were different. I swapped in the older one to get around this problem. The offset on the older one is apx 3/4" and the newer one 1" (the rusty one).
The hole spacing is also different and there is no provision for the wipers at the top of the windshield in an 81 hardtop.
Is the 81 on the bottom in your picture?
It looks like mine including the rust!
Found the problem Smurf thanks to your suggestions. The front header bar had been moved ahead 1" for some reason not known. It was hidden under the headliner and old holes plugged. Will let you know how it fits after I put it back on.