Hey Lew good choice.
If I recall, Lowrance power cable is Red/Black/White , the white should be taped off as it is for an external speaker which is not used on your unit.
If you want to do the best possible install then I would recommend a few things that minimize interference and improve reliability:
1) run a seperate set of power wires directly to your battery -reduces interference
2) use tinned & stranded 14awg or better - withstands corrosion & vibration, thicker AWG reduces voltage drop over longer distances, more strands = better vibration tolerance
3) measure out total length of the red & black power wires + 25% and tie one end to a fixed point and put the other end into a drill chuck - use drill to twist them together - reduces crosstalk interference
4) run power & transducer wires along the oposite gunnel of your boat away from the engine & other wires - reduces interference
5) fuse red wire close to the battery terminal e.g. 3amp - for saftey
6) solder, paint w liquid tape and heat shrink any connections - withstands corrosion & vibration better
Good Luck
Ted