Denon DP-60L clean up

I picked up a DP-60L about 5 months ago. Works perfect and everything on it is in great shape, given its age, but there is some "shading" (I hesitate to call it staining) on the tonearm tube, the headshell, and the metal ring around the platter, just the metal parts. It's nothing horrible but I'd like to try to clean it up a bit.
Maybe it's from cigarette smoke? What can I clean this with? Thanks in advance.
I have a DP-60L as well. No stains on the arm. The arm is anodized aluminum some of the early anodizing had a problem with UV light and adheasion. There also could be a clearcoat over the anodizing. If stained between coatings it cannot be cleaned. It should not affect the playing.

Since you have a Denon DP-60L Does your power cord plug into the turntable?