Finally upgrading my Hook 7 to a HDS 9 live. Anyone have any experience with the placing of the 3-n-1 transducer for best results? My Triton 18 TX does have the welded pieces under the rear transom area. The Hook 7 picks up a signal up to 18-20 MPH before losing it. I would like to improve that if possible. Any help/suggestions would be appreciated! Thanks!