So I cruised out to our local large marina to get my tanks pumped out before winter. Pulling up to the dock, I idled back to neutral but was still going forward too fast. Threw both engines into reverse but wasn't slowing. Gave it some gas and the starboard engine stayed in forward and sped up while to port went into reverse. Needless to say, way too close to the pier and the 3207 bumped into the end of the dock as it spun sideways to the starboard side. Bounced of the floating docks and back into the open water. The marina owner is yelling " my docks " and I'm yelling " my boat is stuck in gear". Line everything back up and try again but still the starboard engine will not come out of forward gear. I threw it in reverse again and tried the throttle but it only went faster in forward again. Luckily was stopped by a wooden retaining wall. Needless to say, the most humbling and humiliating docking experience of my life. Not sure of the damage until I get it pulled out tomorrow. The mechanic comes down and finds that the shifter cable has popped out of the retainer. We think this an easy fix until we hook everything back up and start the starboard engine only to find that it immediately goes into and stays in forward. If we pulled it back into reverse, the motor would die. The shifter cable is working and you can see the lever work from forward, into neutral , and into reverse, all this occurs while the motor is off. The mechanic says the tranny is having issues. Even after 6 or 7 rum and cokes with my buddy, who knows boats, I'm at rock bottom. What is involved in working on a 1987 3207 transmission? The guys at the marina are saying they may write off the boat due to the gel coat damage, although it doesn't look that bad to me and definitely does not affect the seaworthiness. Will have to get some estimates once everything is on dry land. There are lots of woulda, coulda, shoulda answers to what happened, and believe me I've put myself through all of them, but I didn't see this coming and don't know what I would have done different. I'm just looking for answers, if any body has them, about the transmission