RE: O.S. .46 AX Shims
Ed, I think your definition of "blueprinting" is off a little as far as engines go. When someone talks about blueprinting an engine (of any kind car, boat, plane) it simply means to return to the specified measurements for the engine when it was manufactured. When someone says they built up an engine for a hot rod and states the engine was balanced and "blueprinted", that's when people are blowing smoke... Since you have to add/remove material to balance an engine it is no longer at the measurements it was at when new.
If your OS or Nelson or whatever is "blueprinted" then it's as stock as it will ever be, and after 2 races it's not "blueprinted" anymore just because of wear and tear.
Just the .02 worth of a guy who wasn't always a computer geek.