Got the medium duty Perko switch. I have a dedicated battery (1) for electronics that goes to a 6 fuse bus with electronics attached and a dedicated battery (2) for cranking and console accessories (livewell etc). I see that i need a hot from electronics battery to position 1 on the switch. I need a hot from cranking battery to position 2 on switch. I need a hot from motor to common on switch and a hot from electronics bus to common on switch. I need a "common ground from each battery, the motor and the bus correct? Where do i get this ground post and where is the best place to put it. Switch will be right beside batteries on the rod box.

Thanks