Tonight I futzed around some more trying to get the right aileron bellcrank to work better. Removing the bushing from the bellcrank, I noticed a series of shiny bands on the bushing where I assume the bellcrank is dragging on the bushing. I rigged up 5 washers and a jam nut so I could chuck the bushing in my drill press without the chuck marking it up. This helped a little, but I never could get the bushing chucked up squarely again after that first time.
I also ran an 0.374 reamer through the bellcrank, but I couldn't really tell any difference. The bushing measures out at 0.375, so I didn't really expect a lot. What helped the most was turning the bushing around in the bellcrank. I guess that orientation more closely aligns the irregularities in the bushing with the irregularities in the bellcrank.
The bellcrank operates MUCH better now, but there's still room for improvement. I think the next thing I'll try (tomorrow) is to clean all the grease off/out of the parts, reassemble them, and spin the bellcrank around the bushing to "remark" the high spots on the bushing and concentrate on them by hand with strips of sanding belt and scotchbrite. I'll make every effort to go at this easy in an attempt to not make the bushing too sloppy.
The bushing IS sufficiently longer than the bellcrank. It's NOT dragging on the ends.
Shiny bands where the bellcrank is dragging on the bushing.