Hello, I have a 331 with the liveaboard layout where the main panel is to the rear of the starboard entrance and held on with just two screws. I removed mine a few days ago to see how to replace some switches which are beginning to corrode. Interestingly, the panel had about half a meter of spare cable so that I could rest it in on the entrance step.
For the builder to wire up the panel with such a short loom doesn’t seem sensible so I wonder if the loom on yours is held in with a cable tie? Another option is to remove the shortest cables if you can get your hand in until you have sufficient access.