THE DEPTH SOUNDER ON MY 82 CATALINA WAS DYING. AS IT WAS DATA MARINE AND THEIR STATUS IS UNCERTAIN I SWITCHED TO STANDARD HORIZON DS 45. THE FIT IS PERFECT AND HOOKS UP TO THE OLD POWER SUPPLY. AS FOR THE TRANSDUCER I GLUED THE NEW ON IN AT THE SAME APPROXIMATE LOCATION AS THE OLD THRU HULL ONLY ON THE OTHER SIDE OF THE CENTERLINE. WORKS GREAT. THE DAYS WHEN YOU HAVE TO PUT A HOLE IN THE BOTTOM ARE DRAWING SHORT.