Currently my garmin 73sv transducer is mounted at the back of the boat with the screen mounted at the port console next to the wheel.  At the very least I’m going to move the fish finder screen  to the bow.  I may mount my striker 4cv at the console so I have a way to check depth.  
 

 

if I wanted to mount my transducer on the bottom of my minnkota terrova.  How do I prevent my transducer cable from being tangled up on the shaft of the trolling motor?  Is there some sort of after market swivel system ? I actually have a transducer in the trolling motor. I forget what minnkota calls it.  If I use the transducer in the trolling motor I’ll loose the down scan and side view. 

I had a Precision Sonar mount on my Ulterra.

 

Cornfield Fishing Gear makes basically the same type of system as well. 
https://cornfieldfishinggear.com/product/cable-save-r-cable-protection/