I'd be concerned about too deep a backspace if you're running the 'standard' width 56" flange to flange measurement rear axle found on many of these cars.

I tried a pair of 7 1/2 by 15" with 4" backspace on my 55" wide rear axle 32.
They fit ok, but the 235/80R x 15 tires just cleared the outside the frame 4-bars.

Along these same lines a pair of 10" x 15" with 4" backspace CenterLine wheels with 1" wide slicks fit my 31 on 32 rails roadster - 56" rear axle - running inside the frame 4-link just fine.

Both cars have nine inch Ford axles and 11" drum brakes - 1 3/4" lining on the 31 and 2 1/4 lining on the 32 and clearance on both styles of drums was not a problem.

The 32 with its usual 10 x 15" with 3" backspace wheels and 285/70R x 15 tires.