Adding for completeness sake, that site is out of date for my state. Street legal UTV's and mini-trucks are called "Multipurpose vehicles" in Wyoming and can be registered to operate on streets and highways. They even issue these nifty little Wyoming license plates that are UTV sized. The requirements are in the linked PDF.

Funny side note, my state even has a picture of one of the Japanese mini-trucks in the PDF. [1]

I think people should look up the DoT website for their state to get the current legal requirements for street legal UTV's and mini-trucks.

[1] - https://www.dot.state.wy.us/files/live/sites/wydot/files/sha...