I have a lot of fun riding my wife's XR80 and would love to be able to get a plate for it.
But Alaska State Law clearly states that if the bike wasn't sold new as street legal it cannot be made legal.
One fellow even went to court over it but lost.
One suggestion I offer for your bike is to put clear vinyl over the newly painted frame tubes so your boots don't rub the paint off again.
I did this on one of my bikes to protect the new powder painted frame from boot-abuse.
It is the clear vinyl mask that is put on the front of cars to protect the paint from chips.
You could also use colored material of course.