Where to mount si transducer?

I just received my 997 and having trouble locating a spot to mount transducer. I have a 17.5' aluminum boat and was hoping that some of you that have one mounted on your aluminum boat can give me some ideas or maybe some pictures on where you mounted yours. Any help would be appreciated.

First thing you need to do is get is a transom saver. The manual will say which side to mount and how far off center. Center the transom saver on that spot with it up just a hair from the bottom of the hull. Take a yard stick and place it straight in line against the hull with where your thinking on mounting the td with just a bit of the stick hanging out. "All" of the bottom half of the transducer needs to be below that line if your going to use it at high speeds. Check to make sure the yard stick doesn't hit any ribs and best not in line with any row of rivets. With the transom saver if you want to test other spots , no extra holes in the boat.
Some of the guys are buying a $30 dual beam and a Y cable so they can mount that $250 side scan transducer up a bit so on plane if you run over some thing you don't smack it. I'd put a second transom saver on the other side and mount it there. With the Y cable the 200khz/86khz part of the side scan transducer is rerouted to the dual beam and takes it places.
If you have a deep V hull, you might place the dual beam transducer in a spot further from center than the side scan so the side scan sits lower even though its still not clearing the bottom of the hull so when its looking out at 90° its just below the dual beam to prevent blockage. It might look a bit off center with the two but the only time you'll see it is from the back of the trailer.\
Hope that made sense.

WarrenMN

Thanks WarrenMN! I already purchased the transom saver. I am having the problem with the 15" off center of motor. 15" puts me right behind a rib and can't mount any further out because of a factory trim tab that sticks out. I may take your advise on the dual td and y cable. I will hate myself if I ruin that $250 unit. However, with the si unit mounted higher wouldn't it pull out of the water at higher speeds? Or is the dual beam unit the only one that has to be submersed halfway? Thanks again for your help, it definately put a light on things.

I have an alluminum boat and im 15 inches away from the prop, not 15 inches from the center ,mine is a deep v , the only problem I see is the contrst of the depth finder is darker than I expected .