Last night I came home and Luke was in the shop making air filter mock-ups that were similar to dimensions found in some air filter guide books. Here are two of them;
Big one in projected air box intake area;
Small one in projected air box intake area;
Conclusion; we need Goldilocks to find us one that is "just right"!
Luke took additional pictures of other bits he was working on yesterday, I'm sure he will post those soon with more commentary.