These may help -
As you can see, while the cars are just about the same width, the Lionel/MTH State car is considerably taller than the 1:29 Aristo-Craft car. Note that the floor lines of both cars are pretty well matched.
I can tell you from personal observation that the Aristo-Craft car is a great match for the 1:29 USA Trains J1e Hudson, but it overpowers the 1: 32 MTH J3a.
Cheers,
- Mike