I installed a Startguard on my JC in 2015 since my electronics were shutting down when starting the engine. The Startguard never solved the problem altogether since it wouldn’t work when the internal battery wasn’t fully charged and now it needs to be replaced. Instead, I’d like to have my batteries rewired so I have an isolated “house” battery that would power the switch panels and electronics and a starting battery. I’d still like the ability to combine batteries in the event one is run down. The system should have the ability to charge both batteries as needed. I currently have 2 8D batteries running through a 1-2 or both battery switch to the switch panel. What is the best way to execute this? Anyone have an easy to follow schematic?