Planning to install an Icom M802 with antenna tuner for a 23' whip antenna.
My mounting plan is to be on top of the main cabin with three point guy
wires, far away from the Radar and VHF.
All my electronics are grounded to a central point and the chasses are
floating and centrally grounded too.

Planning to share the windlass 70amp power supply for SSB primary power
which is on a separate battery but will be interfacing with the NMEA buss
and GPS equipment that shares the House Bank!

What advice do you recommend for grounding and antenna ground plane!

Will there be interference between electronics on different Batteries? If so
what can I do!