Garmin and lowrance are competing company’s. I doubt they would let the autopilot fully work with lowrance. Have you tried to find out what the cheapest garmin chart plotter that’s reactor compatible would cost? Maybe put a second graph by the drivers console some where. You could save some money by not buying the ghc 20 controller that way. The other thing is on Lake Erie even during the week. Good chance because of boat traffic or wave direction. You will not be able to follow your track anyways. You will end up changing course some. Nice thing is to setup a few of the buttons for 10 degree step turns. Instead of say 5. Where you will always be pushing the buttons allot more.