The 1957 35 horse power gearcase must have the 0302528 "gear case retaining ring" facing the right way. One side is flat, the other side is tapered. The flat side must face the rear to take the thrust of the reverse gear. If reversed it may not drop fully into the recess. Further, it may pop out when shifting into reverse, allowing the reverse gear to push back until stopped by the tabs on the 0392743 thrust washer. This will damage the oil seal integrity. This error in the 75 horse V4 results in the loss of prop, prop shaft, prop shaft seal retainer and reverse gear. . . 🙁
