Sea Ark aluminum.
Tlow, what kind of boat do you have?
Try to keep it inbetween strakes (if any). You may want to get another dual beam ducer to run deeper than the bottom of the boat. Keep the si ducer above to prevent damage from a stump. I think a replacement would set you back $250-300. Also, mount as far from the motor as possible. This will help prevent any motor wash from showing. Does the boat have any type of inset on the hull in front of the motor?
You're gonna need to put some bells on the tips of your poles. You can't watch that SI and your polls at the same time.
I'd help with your installation but my labor rate is out of sight.
Get Your Grease Hot!