Update - The issue with the shifter seal never really resolved itself, so I removed the shift shaft and checked to see if it was bent. It was perfectly straight. I tried using a spare shift shaft from another KX60 engine and it had the same issue...overly tight at the shifter seal. The fix was to polish the shift shaft. I checked the fit every few thousandths of an inch, and when I had removed enough material, the shift shaft slide right into position. No more binding. I still say this seal had to be made on a Monday, but the fix was fairly easy. The worst part was pulling the engine because the clutch-side footpeg prevents removing the shift shaft with the engine mounted in the frame.