Im re-doing the engine bay and I like to know what I'm taking apart before removing. I came across a relay on forward bulkhead port side, just below trim and tab pumps. Its similar to the fender mount ford starter solenoid and appears to be factory installed. Tracing the wires makes no sense because under the dash is pretty messy and probably not wired correctly. Someone before me was not good at 12v wiring at all.
From what I can tell it looks like a way to connect battery one and battery two together with a switch, not for cranking motors, but maybe something to do with the auto bilge pumps?
The dash has be upgraded to a custom one so if there was a switch its gone.

Parallel solenoid. Jumps the batteries together

This parallel solenoid is used to deliver more power when firing each engine. There is usually a pairing switch on the dash to activate it. Mine is between the port and starboard engine switches. It is factory.

Thanks for the quick replies. Makes sense now. When I got the boat there was only 10g wires from each battery to the load studs on the relay. It was stranded house wire so we know that wasn't factory. Each load stud had 8g wires going to the charger batt 1 and batt 2.
I'll trace the relay coil wires and see where they are.
There is also two 10g red wires on each load studs going to the dash. This is were I thought they were an "always hot"
for the bilge pumps I'll trace them out too.

Where was this switch located on a Bullet from factory?
Btw, I see now it's not stranded house wire, it's jacketed 2 wire black-white motor-home type wire that was used by Cigarette in many places in this boat. I can't seem to find the wires that activates it.
Thanks

It’s not a separate switch on the Bullet. The starter switches have two poles that receive power when you press the switch. One goes to the engine harness/starter relay, the other goes to the parallel battery relay.

Thanks TomZ,

Found it/them. Turns out they are orange and must splice into a single white somewhere in the harness. I've been looking for a white wire. In the right column there is two "ORANGE +"
One taps off the hatch switch with a jumper to the port start switch, to connect batteries for hatch operation, the other is connected to the stb start switch.

The solenoid in my boat had no battery cables on it. Someone in the past must have bypassed it and ran direct to the battery selector switches. It did have the 10g wires to the battery charger though. Good thing I'm tracing everything out, the battery charger was charging the batteries via unprotected10g wires to the helm, then back through the master 10g wires to the circuit breakers on the battery selector panel. The connections were made at the bilge pump wiring. My guess is someone was having trouble with the bilge pumps and decided to run dedicated circuits from this solenoid.