RF drain wire on power cords

[scoffer]

I am refitting my boat with Raymarine gear; a78 MFD, CP200 sidevision sonar, and an EV100 autopilot system.

I have a question concerning the termination of the drain wire. My boat does not appear to have a common grounding point. I see in the manuals that it is permissible to wire the RF drain wire directly to the negative of the battery.

I have installed a new fuse block specifically for the new electronics. It is ran back to an independent battery that will be used only for the new electronics. Engine start and all pre existing electrical components are run off a separate battery (although I plan to set it up so the engine will charge the new battery when running).

That said, can I just terminate the RF grounds with the negative wires from each individual power cord for each individual component together at the newly installed fuse block?