Smitty, I even researched futher on the Lowrance web site and found as you stated they can be networked. I did find my LMS 522 can be hooked to an external antenna of the 3000 series.  I've decided when I make my upgrade I want to go equal to what I have or forward in technology. Your asking price is good and I called my youngest brother in North Dakota, he is very much interested.  He has been unemployed for a month and starts a new job today.  He needs to get a few paychecks in and if ya still have it.  No chance of him using your way points in ND while walleye fishing.