Pumps on a Puma FTD are designed to mount tucked back in against the triangle live well and storage box nook, if you have to move them. Then you can suspend your oil tank over the sump and move the third trolling battery in front of the cranking. You could just run an AGM 31 series battery on the cranking and go with three batteries using the cranking. Worst thing you cold have to do is change it, though we dont think you will have to.