On my Nomad model I installed a shoot-through transducer on the port side, just forward of the engine. I glued a 6” length of 1.5” ID PVC pipe to the hull, with the lower surface beveled so that the pipe is vertical. The transducer sits in the pipe which is filled with water. Placement of the transducer is not critical. My cheapo depth sounder picks up the bottom at about 75ft with this arrangement. Good enough for most purposes.
Willard 40 -Lilliana-Sea of Cortez, Mexico
Willard 30- Puffin- SE Alaska
Tiffany Jayne 34-sailboat- Dancer- SF Bay