Visual Model Radius - How to Read for Boats

Is anyone able to help me find a way to read the "Visual Model Radius" processed through Simconnect for a boat?

As some of you know, the VRS F/A-18E uses this variable to sort through the FSX AI and find the aircraft carrier which it can then assign a makeshift moving TACAN and ILS.

I'm trying to make a new carrier model work with the VRS F/A-18E (Team SDB Enterprise...a rework of the Alphasim). At the moment the value of this variable does not seem to be well known and I am hopeful there is an efficient method to determine this rather than trial and error.