Many thanks for your reply. Right away I notice one big difference between our boats (besides the battery chemistry): You said that your batteries are bolted down securely with a piece of "starboard lumber" and 3/8 threaded rod connecting them to the lazarette floor. The floor of my lazarette consists of several ill-fitting pieces of wood that seem to simply sit there. Underneath them is a sheet of plastic which is over the holding tank area. Thus, I've not been able to figure out how I could securely attach anything to the lazarette floor.