One of the stories referred to collectively as "The Brittle Mastery of Donald Duck", a series of stories by Carl Barks (or his successors) where Donald is the-best-there-is at something... until he's not, usually involving some disaster.
Philo T. Ellic, the rich stamp collector, originally appeared in "Donald Duck and the Gilden Man", written and drawn by Carl Barks, from Four Color (Dell, 1942 Series) #422 (1952). https://www.comics.org/issue/9608/
Donald Duck is not exactly unfamiliar with cleaning clocks, having co-starred (with Mickey Mouse and Goofy) in the 1937 Walt Disney theatrical animated short "Clock Cleaners".
Story is attributed in this issue to Carl Barks; the Barks story attribution appears to have been incorrect.
Part 2 of 3.