Transducer help

Ok, i really hate posting a question that has been answered a million times, and i have searched, but i am a total noobie when it comes to boats. I have a 12ft semi v hull jon boat. I picked up a humminbird piranahamax 220 and i am trying to pick out the best spot to put the transducer. My first question is, does the face of the transducer have to be level or below the boat? I ask because i don't have a trailer for it and i put it the in bed of my truck, put it on the ground, slide it to and fro ect. I also have read about "clean water"?? I am only using a dinky trolling motor to propel it, so i don't get up on plane or make a ton of wake lol. Any helping me?? Thanks, Elliot

If you could mount it on the trolling motor you would be ahead of the game.

Yes trolling motor is the best place, no holes in you boat is a plus

Trolling motor X3 or inside the boat for a "thru hull" mounting

cant put it in the hull on aluminum boats