89 Sailfish
Same problem, leaky cabin front windows-> mildewy monkey fur.
started to pullout the monkey fur intending to just paint the ceiling and walls with a high gloss- way too difficult, lots of glue and the result was a very nasty surface left behind that was not paintable.
Solution, glued it back in place and sprayed 50/50 bleach/water solution on the stained fur. took 3 applications in some places but it killed al the spore and took out all the stains. Looks like a new headliner.
To prevent recurrence i pulled the cabin front windows, replaced the glass with tinted safety glass put alot of attention into reseating the glass in the frame and the frames in the hull -big wide bead of silicone around frame - which I trimmed back only after it had fully cured.
i'm rebuilding the port bulkhead now, but that's another story.