I was fascinated by rat racers at the end of my youthful period in control line. I think the last full CL planes I was working on were a Yak-9 that I finished 40 years later and a full-bore RR with a modified Harter's speed pan, in which I'd bolted a K&B .40. I had a Kilsdonk (I think he made them) tapered, cylindrical tank with a "quick-fill". It was going on it's third set of wings (kept changing my mind as I read the articles) and second tail. The remnants are still up here on my shelf. I also built a tiny .15-powered racer, "Texas-Rat" style, and later, a tailless, TeeDee .049 - powered mouse racer that I still have. The only full sized one I finished was an earlier Dooling .29 powered Harter's "Royal Rodent" with polished pan. It survives because it never flew (too much fun with the stunters). When I retrieved it after 40 years from my parents garage, I was really glad I'd never flown it. Those controls were never free'd up. Gads! It's one thing to watch the "big guys" fly at a Kokomo, Indiana AMA meet, and another just to put one together without advice. I also had bought an earlier Fox "Combat Spl." and a Super Tigre with intentions to fly rat, but life sort of intervened. So there's the story of what I didn't do. Ha!