1) Browse to page #2
2) Open the folder for "Transducers - RealVision 3D
3) Open the folder for "RV2xx, RV3xx Thru-Hull RealVision 3D Transducers
4) Open the folder for "Manuals"
5) Download "RV-2xx 3D Bronze Thru-Hull Transducer Installation instructions 87335-4-EN.pdf
Chapter #3: Installation
Section 3.3: Selecting a Location
Page # 18 shows a diagram of some good examples based on boat type.
Most look somewhat inline. I'd find the spot in the hull with the most access for installation and running wires.