I assume it has the same finish as my beige 201K23 (the cast aluminium version). I have used microfiber cloths and sewing machien oil. On stubborn discolorations I used cloths wringed up in soapy water and there was no sign of damage to the paint. The beige and green colored machines (that came after the black shellac with gold decals in the 50s and early 60s) are a form of hard enamel paint. It should stand up to reasonably gentle cleaning methods, but some types of oil (like vegetable) can damage it if left on for a long time (turning gooey). You could try a resin type car polish (the liquid stuff in bottles that dry to a white we buff off); it should lift up quite a bit of dirt and grime from worn paint and perhaps save it.
Last edited by Mickey2; 02-09-2017 at 04:25 AM.