No problem at all. Glad to help out a fellow vintage Trek owner!

Ahh... I see you found some!! It may be only a turn or two on the limit screw that is slowing the chain down. Look from the back of the bike after it finally drops, and see how far over the derailleur is past
the small cog towards the dropout. If it is a little to the next biggest cog, loosen the limit screw until it's even with the small cog. A delayed shift on the top or bottom end is almost always a limit screw issue, or in rare cases on forged drops a slightly bent hanger. Judging by the condition of the drops, probably the limit screw. It could also be an accushift issue, but that derailleur looks like one made after they ironed out the problems.,,,,BD