At least you don't have 'shaggadelic' mohair hanging off the overhead! I remember a Reinell 26 that did....
Some of the teak cleaning products around might lighten the finish first.. lots of the older 'oiled teak' interiors get pretty dark over time.
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)