TobyGadd Thanks for the info! Luckily I have learned the hard way to leave the hammer on the wall when it comes to bicycles (use it plenty on my dirt bike ) so haven't damaged anything. C-clip is in good shape and there appears to be a little washer between it and the bolt head, I guess to reduce friction. Good tip removing the seat posts to clean out the frame, I'll do that!

Hopefully I won't need Mel's help (on Kauai, so far away) but that's a great thing to know!
Btw, does anyone know what year the T-2 started? And how to tell the difference?