I'm needing a little advice. My new transducers for my Raymarine tridata use a 2" hole and mount flush against the exterior of the hull. The originals are 1 5/8 and sit in a countersunk recessed hole so they sit even with the hull. If I put a 2" hole in the center the flanged hole the new unit would catch the edge of the recessed part. Ok now you're lost an have no idea what I'm talking about, but it would just catch the edge leaving a big void behind it. Anybody ever deal with this and what would you do? Is it thinkable to sand off 1/4" of the edge of the transducer so it would go into the recessed hole?