This old Marlin came in for a setup in open C (C, G, D, D, G, C) and to have some electrical issues looked at. It was clear it hadn’t been cleaned in a while and there was a lot of dust on the bridge and the fretboard was dirty, as were the frets.
The pots weren’t in great shape and the output was intermittent so I replaced them with fresh parts. The nut was too low so I swapped it for a re-conditioned one I had left over.
This guitar could do with a lot of work on the frets but the work would be much more than the guitar is worth, I would also suggest making up a custom set of strings for this tuning as some of the strings are really baggy.