We've got an '88 model 3807 that we totally love, but the AC ducting off of the Salon unit continuously sweats to the point that dripping water seeps back underneath the aft cabin walls and wets the carpet. I've been able to get insulation around all the ductwork for the aft cabin unit and the v-berth unit, but the way that the duct is chased inside the wall pocket separating the salon from the aft cabin vanity desk is driving me crazy! The flex duct appears to be squeezed into a flattened oval shape just off the unit inside the aft cabin closet where it has to go through a ridiculously narrow, oblong cut into the starboard side riser or stair framing(?) before apparently then connecting to a flattened box that sneaks up inside the wall pocket to the vent on the aft salon wall near the ceiling.

Does anyone know a way to access this duct without having rip through at least three different sandwiched layers of wall plywood? Going through the finished salon wall would be disastrous, as I'd never be able to keep from scaring and damaging it. I first tried removing the vanity desk framing, then pulled off the mirroring to access its plywood behind, but then removing that sheet only found MORE plywood?!

Help please?