Hi all, I am a newbie. I own a 2007 nitro 591 with a 150 optimax. I am interested in installing smartcraft sc1000 tach and speedo. What is involved to do this? My manual says it is compatible. The main question is: Is the wiring harness under the dash? Do I need a harness to run from the engine? What are the components needed for the install? My boat currently has standard nitro guages. Any info would be greatly appreciated! I plan on buying on ebay so I would like to know exactly what I need before I proceed. Thanks