Thank you for your reply. Let me give you more detail to my situation and see what you recommend.
I have the DI transducer currently transom mounted. Over the course of a year, I have remounted and adjusted the transducer 6 or 7 times, only to find one acceptable mount configuration. Currently, I have the transducer mounted to match the 20 degree angle of the hull (which the folks in service tell me is incorrect), and aligning the seam with the bottom edge of the hull. I get the best on plane reading from this configuration, but I often still lose reading in choppy or otherwise rough water. I am also obviously reading the bottom 20 degrees to Starboard of the boat. The last issue would be the same if I mounted the transducer to shoot through the hull, not to mention, also the inherent signal loss.
If I mounted the DI transducer in the hull, how do I overcome the angle issue? I understand the loss of sensitivity in the 2D range is not perceivable, but what about the DI image? The boat had a HB from 1993 shooting thru-hull previously, and was actually working just fine when I removed it, so I know a shoot through transducer will work. Are there any aftermarket alternatives to using the DI as an in hull mount? Thank you for you help.