Yes Timbo, a tumbler is a must. Certainly makes light work of polishing posts, screws and other metal furniture.
Not a great deal of progress today...Groundhog day with underside mechs'. Each removed, cleaned, lubed (where required), new sleeve....
Interesting to note - I find some of these components 'tell' the story of the pin. On games which have seen a busy life out on route, the metal components show this history, with gouges, wear marks and general wear and tear to the point of disposal.
This WCS however after a light clean they look like new.