Down Scan Adjustment And Installation Seem Complicated

My Humminbird unit has instructions for installing the transducer on the transom and it sounds like rocket science in their manual. They comment about transom angle in degrees, 15 inches from the prop, then there is some diagram showing angles for the transducer.

Is there an easy way to do install it without getting lost in all the Greek instructions?

Also, there is a recess at the bottom of my transom. It's something Tracker had this year on their boats (something about planing out better and "hole shots"). This is where the factory transducer is mounted but there's no way I could mount the new transducer 15 inches left or right of the prop. Should I mount it there or go up on the transom?