I went to Mermaid A/C in Fort Myers, FL. They are very helpful. Got measurements for their unit. Made a box the appropriate size. Built a shelf to support unit. All going well...until, I went up there for final consult when I was told I needed a 4" splitter on the air going out to achieve appropriate back pressure for unit to function properly. In short, there was NO room for that in ANY configuration. They would not guarantee the unit would work properly. My response was I was not going to drill 2 holes in the hull, spend close to $2,000.00 and not be assured the unit would work properly. Result, no A/C. I don't know why I could not put a damper, like a shutter, in the way to create back pressure (lack of freezes up unit if I remember correctly). End of project. Could have located unit in aft bunk, but that had it's own problems.