Does any one know how to access the rear state room air conditioning duct work above the bed area. I would like to clean or replace the duct due to an odor and also condensation that drips through the over head reading light fixture. It seems that the large grill work over the bed should be able to be removed. I can not find any way to access the mounting screws that hold the grill in. any help would be great. The boat is a carver 466