OK, i went out to the boa last night to 'trace' the wiring.
3 wires are coming out of the 'original box '.
1 - to transducer under cabinet in cabin - maybe depth ?
2 - running under the floor on port side - maybe for speed ? ( wind or boat ) ?
3 - To distribution panel
# 1 above -
the wire leaving the 'original' box and then go to another 3x3x3 box ( very small ). no labels, no ID#, nada... then leave this box and then to the transducer.. very strange.
The gauges only light up - no numbers for depth or speed.