I would buy a Ram Mount and mount the GPS/depthfinder to the front and
outboard side of the drivers side of the boat. I would also mount the GPS
antenna beside the depthfinder (on the same bracket) so it could be used
from the front seat as well as the drivers seat.

That is exactly what I have - but it would be a lot easier to have the display
up front where the front depthfinder is so I would not have to strain to see
it. The console is sevreal feet from where I fish in the front of my boat. I
could also stay facing forward.

Seems if I am going to have two depthfinders anyway, a slave unit would be the
way to go.
Ronnie

http://fishing.about.com