Help on Transducer type & location? for 388 Hustler
 

I bought a Garmin 942 Echomap UHD with (shoot through)transducer and having trouble finding a place where it will work. I'm wondering if anyone has tried putting a second shoot through hull transducer in one of these boats? Or drilling a hole in the hull and placing an in hull transducer?
There is a factory cutout on the starboard side under the engine for one, which the boat came with a Livorsi 2" digital gauge/transducer, but that cuts out at 19 mph before I even get on plane and is useless.
Anybody shed some light of experience here? : )