I have a 24' pontoon boat with 19" logs on it now. I found a 18' log with a diameter of 23" that I want to add to down the middle. I know about leaving enough space between back end of new toon and the transom so the motor won't cavitate. And I know about keeping it even or ahead of the existing toons, but what about the diameter difference? Will the larger log cause the boat to teter back and forth, side to side? Or will the shorter length be less boyant than the longer toons, thus not causing this problem? Thanks so much for your help with this, Dave