work on renovating my Happy hunter is progressing but I need to decide on the battery and make location for it in the hull so that I can get the right amount of ballast in before proceeding any further .The question is what battery to use .The Hull has 2 motors fitted with gearboxes ,I think the motors are 540,s but there are no markings on them.I am thinking a 12volt SLA battery but would welcome some advice