9.00x14 on 14x6.5" wheels.
The best long-term situation would be with some 15x6 wheels, P225/75R-15 tires, and Chrysler 15" wheel covers. The power disc brake cars in '66 used 15" wheels to clear the brake calipers. Otherwise, the Coker BFG 1" whitewall 9.00x14 repro tires would be the best option, from size and cosmetics.
I believe that Hankook builds some P215/75R-14 whitewalls, which is the size the non-factory a/c sedans came with. On the heavier wagon, you'd need to make sure you did NOT follow factory basic inflation pressures! Use more like 35psi all around.
As common as the H78x14 size was in the middle '70s, many brands were moving away form them back then, heading toward the "new" 15" wheels for factory disc brakes. And now, the tide is shifting more toward 17" wheels!
So, look around and see which way you'd desire to go.
CBODY67