The C-series unit you have is NOT networkable - There is no such thing as a "secondary" display with it. You'd have to have a full set of
cables at both locations - this isn't really a problem for
power and
SeaTalk - just a matter of finding the right
cables and
wiring them in since you can tap these anywhere. If you have NMEA0183, it's also workable since the wiring is pretty simple. But, If you have
radar, depthsounder, or
weather modules, then it will be problem as these are point-to-point cables.
I have a C70 at my helm. I just do my planning sitting at the nav station on the computer, then transfer to the
chartplotter via NMEA0183
network or CF cards... Works for me, not sure if it will
work for you, but it's an option.