US Military inter-War Equipment

[Onebigriver]

Hoping the historicals can help with this one. I want to do some pulp/cthulhu skirmish scenarios, but I'm having difficulty finding info on what equipment, especially vehicles and artillery, that the US were using in the 1920s. what references I can find say that rthey were still using alot of WW1 equipment, but were they still using WW1 trucks and artillery? Were the few tanks they had still the Renault FT-17s? I've got in mind the scene in King Kong when what I imagine is a National Guard Coastal Defence force are mobilised to take on the ape.
Hope you can help.