Fish Finder Rig on a Float Tubing

Can anyone help me? I use a U-shaped float tube but now I have a pontoon boat. I have a regular fish finder (Fishing Buddy is better suited for float tubes). I don'r know whow to mount it. I have some straps made to secure the screen to the tubes but what about the transducer? How and what to I secure it to?

Heres something I found at this web site http://www.fkpfishing.net/FeaturedReviews/review.Piranha.htm