Thanks for the info, folks. It was a great help. I also ran across this video tour of the underside that shows all the belly pans in place:
https://www.youtube.com/watch?v=S0dEXoWRCi8
I knew I'd strike pay dirt if I kept on chipping away at it.
Main pan, front:
Small pan, rear:
Before I removed the two pans I snapped photos of them similar to these, and then somehow accidentally deleted them. "No problem," sez I. "It should be fairly obvious where they go." Famous last words. I felt like a prize sap. Anyway, thanks to you guys' contributions and this video tour, I'm golden.