I looked up the Arizona law for MB and was pleasantly surprised at how lenient they are.
I see we thought you were located in Florida and just did not want you to wast your money on something you could not ride.
But looks like your are in Arizona and there laws are just like Texas.
Most states does consider any Motorized Bicycle 50 CC and higher as a motorcycle and you must have a license, insurance , and so on.
But most cops would not know a 49CC from a 66/80 CC , so if you do get stop and you have a 50CC or higher engine play it safe and tell them it is a 49CC, that should save you any headaches, and keep the law dogs off your tail.
Enjoy your new build and don't forget to post pictures we love new builds.