I have an older Ranger that has 3 steps on the transom.  One of the steps has the livewell intakes and the plug with no room for a transducer.  The second step looks like a good spot, but on the right hand side, there is already a transducer.  Would it be possible for me to mount the new transducer inline with the outboard on the middle step and get good readings, or should I just remove the other transducer and place the new one where the old one was?  The length between the second step and my lower unit is 9 inches when trimmed all the way down.  The boat has no jackplate.

Do you have a shoot-thru transducer for on-plane depth reading?

Do you use the present transducer for on-plane depth reading? If so does it work all the time?

Do you want the SI transducer to give you on-plane depth reading?

Most SI and SS users do not mount those transducers at or below the hull bottom especially on stepped hull bass boats.

  I use the other transducer for readings from the trolling motor, though the old depthfinder broke, so I should probablly just remove the old transducer.  I don't really care about  on plane readings.

I have a skeeter like that with the two steps. I mounted my HD SI transducer just to the right of the engine on the transom. It will not read at speed but i did not care. I have other units to do that. I was only interested in the unit reading while idiling around in the SI mode. Here is a pic.

In that case mount it like FFD did but put it closer to the motor mount/center of the boat.

That will lessen the close object echoes that make those ??????? lines next to the centerline of the SI screen.

You can add a shoot thru for on-plane 2D readings of you want. Its just a simple connection with a Y cable and an epoxied 2D transducer in the hull next to the hull drain. That is the set up that most use.