I have a Crestliner Phantom 196SST aluminum boat equipped with 140HP Johnson outboard motor and 15HP Johnson outboard as a kicker motor for trolling. My problem is I cannot get the kicker motor to troll slower than 2mph . I am looking to buy a trolling plate to allow me to go slower. Should I look for a Trolling plate to be mounted on the 140HP or the 15HP motor when I intend to only troll with the 15HP motor? Also which trolling plate would work best? If it is mounted on the 150HP motor it would have to be able to be released when using the 140HP for high speed. When running at high speed the 15HP motor is tilted up to a locked position with prop out of the water. If trolling plate is mounted to the 15HP motor would a permanently fixed trolling plate work better than the 140HP releaseable trolling plate? Thank in advance for your recommendations and experience.