Thank you Bill and Alexandre. Bill I will call you on Monday.
In advance of that, in answer to your question, I do not know what batteries were on the boat originally. I don't know when Amel moved to AGM's but I thought it was in the 54' but probably wrong on that. This boat is a 2004/ built late 2003. This boat already had a Balmar voltage regulator on the 175 amp alternator. It didn't work. I repaired all that, verified that the alternator was functioning properly with the regulator, added a Balmar Alternator temp sensor and plan on a Balmar battery temp sensor during the battery change. The Balmar regulator is easy to program. There is a Samlex charger and two Xantrex inverter/chargers that appear to have replaced the function of the Dolphins (still there). The Xantrex are AGM capable, I don't know about the Samlex 2440 as yet.
The AGM's should be 1/2 inch wider than the current wet cells and just slightly taller, About the same length, looking at that as I decide which battery make is going in and verifying the size. But yes Alexandre, my compartment is larger than yours, it's like Bill's, with a 12 battery rig.
James
s/v Longbow SM2K Redline #418