They were under the locker until (I think) 2004 maybe 2005 and then they moved them to under the v-berth too get better airflow

I have a 2000 and it's below the v birth

Mine was below the locker in my '02 340. I had to remove the fridge to get to it. Turned out my issue was a loose wire in the control box. Now THAT was a ***** to get to! Behind the speaker panel on the port side.

My A/C from day one never really cooled ... what I call properly (being an HVAC&R guy). So I made a driveway water supply hook-up, ran the system in the driveway, check freon pressures and all. The I found that they crushed the 5" supply duct that goes to the high wall supply above the breaker panel. So I bought a "Y" and added another supply lower (the only place was in the side and couch level) and know there is no problem cooling down the cabin. Turn it on when the cabin is 90 degrees and in a matter of a half hour to 45 mins --- it's down to 72 degrees

AC unit
 

I installed a 9000 Btu in my 380 and it is a meat locker. Way to big. I put it under the V-berth It fit like a glove. Ran all the wiring and hoses down the port side behind the sink and locker. Put the pump in the engine compartment with a valve so when I lift the boat i do not loose prime.

You can look at my ac unit in my 34 powerquest the cabins are about the same, I live down the street from you in mchenry , my boat is in lake zurich inside