The IC-78 is a commercial land based SSB unit.
Normally used in places like Australia of Africa for long range, land based comms.
It is not a marine unit and is not approved for use on the marine SSB frequ's.
The Ham/Amature kit is also not aprroved for marine use.
The 78 and 718 are in deed based on the same unit.
The M802 is, at this time, the only marine SSB form Icom.
It is not approved for the EU market.
The M801 EU Marine SSB was showm at METS, is at Paris next week and will be launch in the UK at London in January.
The M802/801 are designed and built specifically for the marine world.
Our land based and or the Ham HF kit is not.
Hope that helps