1981 Grand Banks 42 Classic Aft AC ducting help needed...

[Knot A]

Hoping someone can help. We have a 1981 42 Classic where the previous owner installed a new Dometic AC unit and re-ducted it into the port aft corner of the port bunk (on a wood tower coming up through the panel on the end of the bed platform). It works, as it is coming straight up from the AC unit below the bunk, but it is an eyesore!
The original supply is in the center of the aft bulkhead but it is sealed shut and the ductwork is gone. We are hoping to find someone with the original ductwork on their 42 that could explain how it should be ducted and hopefully send us pictures so we can put the system back to how it should be.
Fingers crossed someone on this forum has the solution...we've been trying to figure it out for months!
I have tried the Grand Banks Facebook group also but no luck there.

 

[Steve1.0]

On my 46 cl, the ac is under the stairs into the aft cabin, however the ducting runs to port thru cabinetry housing the exhaust pipe as well. From there it is run up the aft wall of the hanging locker. this portion is constructed of wood (teal I presume) with a thin foam insulation layer glued to the inside. Its cross section measures approx. 2.5" x 6-7" to the register which discharges from near the cabin top, aft into the room. Ducting from the ac is typical 5"? insulated flex ducting, tied into the box sections via a face mounted flange. Not the most efficient flow path, but it will freeze me out if set low enough. Will try to get a photo if desired.