Look see the angle the the transducer is to the bottom of the hull. You should be able to put a yard stick against the bottom of the hull forward of the transducer and the yard stick should line up just a bit higher on the TD than the mid line. It should face a touch forward so the water going under the boat hits the bottom of the transducer. You can try too much once and see if it makes any difference.
WarrenMN