The Furuno NavPilot 300 is focused on the center console/outboard market. It would be preferred for your install as long as the needed pump stays within the allowable limits of power draw. Is has better pricing and offers the Bluetooth remote. The 711C is needed for clutch, solenoid, larger pumps, or sailboat support. The main control of the 711c has a knob and the NP300 does not. You should find the steering cylinder for the engines. If you have more than one you add the total cubic inches needed to determine the properly sized pump. If you don't currently have a suitable source of heading on the boat you would want to get one with a compass like the Navpilot 300/PG. You can get a full package with compass and pump if you verify what is needed like the NavPilot 300/PG-S or Navpilot 300/PG-M. It is unlikely you would have any need for the Navpilot 711C for your boat. The Navpilot 300 series would be the most cost effective but the 711c support both 2000 and 0183 and more multi-platform flexible.
