Depending on your expectations and where (geographic) you plan on using, 5-6K BTU may be a bit on the light size. Are you just looking to cool just your V Berth or the whole cabin? I have a 16 K Polar Bay unit (now part of Dometic). You can see some pictures of location, etc. at this link [URL="http://catalina36mkii.blogspot.com/"]Carina Upgrades[/URL]

Here is another link you can view several other installations from our cousins @ [URL="http://www.c34.org/wiki/index.php?title=Interior"]C 34 [/URL]site. Lots of good info there.

I have a Cruis air 16k that came with Spanki, even it won't cool the whole boat if its over 90. We will put in a Mermaid 4 or 5k before we move to the coast as we plan on only cooling v-berth and want our Honda 2000 gen. to handle the load, it will on the ECO setting but won't run the 16k unit. I.ve installed two Mermaid units on other peoples boats on this lake, its not hard. The really neat thing that Mermaid has (you can buy it for any a/c unit) is a condensator valve. It connects a tube from the condensation pan on the a/c unit to the cooling water for the a/c that causes that water to suck the condensation out of the pan and discharges it with the cooling water instead of in your bilge. It uses a ventur'e effect and the only drawback is it should be cleaned out once a year, takes 1 hour to install and 20min to clean.

I have the Mermaid system in mine and I could not be happier with it. In fact it is 26 deg out right now and I am sitting in a 70 deg cabin. Mine is installed under the v berth and it is moderately quiet. I should say the noise to comfort ratio is completely acceptable.