2003 Mercury 115HP O/B has become increasingly hard to shift (never did shift smooth like my I/O) over the past 4 years that I've owned it. When I last changed the water pump the shifting mechanism seem to work very good. I've opened other shift lever boxes in the past and know they can easily be messed up. I'm wondering if someone with similar experience can point me in the right direction before I start looking for the problem. Thank you, Dennis