Yep, my younger cousin next door was signed up, and I got to help him build. This had nothing to do with Revell or Monogram, and in fact what I remember most is that I had never even heard of most of the kit brands at that time, the one standout exception being Aurora. One of his kits was the Aurora viking ship. This probably where I learned of Pyro, Lindberg, Palmer, and other dirty words.
Several comic books of that time ran the printed ad to get you signed up. You just didn't know what you would be getting! Ooooh, but you got a sweet set of Pactra'namel paints. I was jealous.