The Elite 7 HDI transducer can be mounted to the trolling motor with the trolling motor adapter cup.
Lowrance HDI Trolling Motor Adapter Cup f/Skimmer XDCR
The only issue will be that you can not zip tie the transducer cable to the trolling motor shaft due to the shaft sliding in the shaft sleeve. I have seen some using a spring attached to the top of the motor head and attaching the transducer cable to the spring keeping the transducer cable taunt....
It's all coming together and we have you covered @ Shut-Up-And-Fish LLC
From *Sales *Installation Services *On the Water Education & Instructional Trips
we are your One-Stop-Shop for all Humminbird MinnKota & Motorguide needs & more
972 822 9285