This is what a true "RAT" is all about. A TRUE biker who rides his bike every where, never works on the machine except when it breaks down. Usually on the side of the road. The only time the machine is cleaned is when it rains, and the term "Rat" is a reference to a "Pack Rat." Some one who never throws anything away. In the old days these Pack rats carried all they owned on their bikes with them. They strapped on any and every thing they found.
So moving forward in history. It seems that the Rodders decided to capture this look in the automobile world. They took old parts from several cars and put them together to make one car. Some what, cleaned up the pack rat side of the look and entered them in shows. I would have to guess, but I believe some old time biker saw a car like this at a show and thought it reminded him of a "Rat Bike" and the name Rat Rod was born!
The funny thing is, we in this hobby, take bits and pieces from several deferent kits, add some personal touches and spare parts all the time.
We call them MODELS!
The idea of breaking up contest into groups is nothing new. I believe it just makes things easier. I like specific grouping myself.
J2