Hey Andrew; Thanks for the kind words, but I am just learning like everyone else. As far as the Rimfire plugs in your Forster 35, they originally ran V2 plugs, and that is what I would go for in the Rimfire. I have been running the V2 Rimfires in many old engines with 1/4-32 plugs, and they work very well in all of them. I have never had a problem with pre ignition, but I guess it can happen. The only cases I have heard about, was with high nitro fuel, and the old wire type plugs, where on a lean run the little hook wire began to glow which in turn caused the pre ignition.
Really glad to have met you at VSC and hope to see you there again. Sparkers can be frustating at times, but they are so much fun to run. I was glad to see you get in a flight, as that makes it all worthwhile.