1930 Colorado Guest License Plate

I think that the recent question we received and Tom’s response are post worthy:
Hello,
I am interested in purchasing your Colorado 1930 plate and have question.
You state that it is a “Guest” plate.
What is the difference between a guest plate and a regular plate?
Do you know a “Guest” plate can be registered in Colorado just like a registered plate?
I have searched the Internet for these answers and can’t find any reference to a guest plate.
Tom’s response:
A regular passenger plate would have had all numbers.  The “G” prefix indicates guest.  Letter prefixes were used for other vehicle types ; D for dealer, T for truck, R for replacement, and T-D for truck dealer.  Trailer plates probably used a T suffix, but no 1930 plates are known in any collection.

1932 was the last year in which Colorado issued guest plates.  Whether or not one could be used for YOM purposes would probably depend on the whim of whichever DMV clerk was approached.