No drilling on mine.
1. I used the sail mast ram ball for the ff itself.
2. I used the electrical duct seal, and simply squished the transducer in behind the mast post inside the hull - works without any problems.
3. Bought a Stealthcam battery, already in dry box with charger at Academy - $39
4. I slide the battery box in the front compartment in front of the hobie storage bin that fits in that hatch.
5. I just let the wires come up under and out of the front hatch cover.
Works like a champ.
Magnolia Springs, AL
Hobie PA12, Outback and Revo11