I had also asked about cleaning recently, this is the one I was needing to touch up. So as a bonus, here’s a little before/after shot.

The before frets were grimier than they look in that pic. The area around the bridge comes off worse in the photo than it was. All around it seemed clean at a distance, but was actually pretty gross. I wound up just giving the fretboard a good rub down with a microfiber cloth, same for most of the body, and using a touch of Brasso I had around the house on the metal sections. Not perfect but much better.