I split mine up so that the engine starting battery only cranks and provides power to the tach, fuel gauge and hour meter. Trolling motor runs off a 24V bank along with the electronics and lights. I come off the first battery to get the 12V to run the console. That was by my design. I can always get home without lights or stereo, but I don't want anything drawing off of the start battery. My instrument lights operate off the nav light switch. I don't need lights on the instruments until I need running lights to run at night.
2015 Seaark 1872 MV CC Etec-90
Helix 12 CHIRP SI, HB 1199, MinnKota Riptide ST80/i-pilot Link, Bob's Hydraulic
Bitter Gun Owner