I have a humminbird 899 at the console and 859 on trolling motor. How do I link these 2 graphs together? If I do this, when I mark a waypoint on one graph, will it automatically create one on the other graph? Where is a good place to buy one and the best price? May have to PM me about location to buy and best price, so it doesn't turn into an advertisemnet post in this section of C.Com.