Not sure what the motor height should be as I have never reset mine from the way whomever originally bought and set up the boat. It seems to do okay. Any comments would be welcome as I am open to ideas, but thought I would share another perspective.
The cavitation plate is the lower one with the Stingray plastic wing shown in the lower right of the photo.
Trim is set to all the way down (I usually tilt it up just a little if not loaded heavily with dive gear). There is about 1cm of clearance to the bottom of the boat, as the yellow level is resting on the "bottom" of the cavitation plate.
Projectile, could you please share some photos of your elephant trunk setup both inside and outside? I would really appreciate it.