Put it out for member input, along with wheel size option to 7in for B and C. Pretty sure that the results will surprise.

I have a difficult time believing that existing racers want to go out and replace all of their wheels. New people to the sport? That I'd buy much more so.
Your screwing everyone in the class that already did the build.

Well, not really. The new cars would use an adjusted classification calculation. I can agree on the point where it's time for me to build a new engine this winter and not having to worry about the block would be nice. If I fell into one of those who still needed to, I can see how I'd fall into one of those who got screwed. Tough call.