Buddy of mine was changing impeller on a Mercury 115 outboard for the first time. Pretty simple job. After he fought with it for a few hrs trying to get the shifting splines lined back up he gave up and called me. I stabbed the bottom in twice and still wouldn't shift. Took the cowling off the top started looking at the linkage and happened to catch my eye on a shinny piece of aluminum. Dropped in the inspection camera (under the ECU) and found he had broken off a piece from the side of the block that holds the shifter shaft down. Pulled the side cowling off and went to work on a fix, as buying a new block would have been the only other way to fix it. Got lucky and wasn't too bad to fix. As thin as the aluminum tab was I don't see how more people don't break them, just not a good design, but it wont break now