Yes, 1/64 cars will work okay with a postwar layout. Regarding some of the comments above, most Matchbox and Hot Wheels cars are not 1/64. Most of them are smaller than that. But, some of them are spot on 1/64, especially the models of smaller cars.
Some of the Johnny Lightning and similar, higher-end die cast cars at retail are 1/64, but even that is hit and miss.
I'd say buy a couple 1/64 cars and see what you think. I think they are fine, though very different in size from 1/43. The 1/64 cars also fit PERFECTLY on the MPC-era tri-level auto rack.
