Identifying license plates

Factual Questions
1

I’ve been collecting license plates from the Duel truck (there are 8 in total, one is on the back),

https://s1.postimg.org/lf0xlgf8v/dueltruck4.jpg

And the closest I have is Nevada. I managed to find a red 1970/71 with MC on the right side like on the truck. I also found an black single X California plate that’s below all of them.

I’m thinking that some of these plates are fake though like Idaho (the small white one) 4017

Arizona to the right of that that says INT on the left side.

And the square Montana plate to the right of that that says MBC on the top.

What does MBC mean? Is that a motorcycle plate because of the size?

Of all the square Montana plates I’ve found they’re either for motorcycles or trailers. I also found a very rare one that had something to do with the railroad.
Basically this thread is about if some of these plates are made-for-movie and what some of the letters mean like INT and MC and MBC.

2

I’m pretty sure the one in the upper left is from Wyoming. They’ve been using the image of the cowboy on the bucking bronco for many years. Scroll down on this link to see examples from 1937, 1943 and 1962.

I believe MC stands for Motor Carrier.