Hello, I've been trying to remove the lower unit from my 2008 Mercury 50 two stroke outboard. I have read several forums and alot of them say that the shift shaft is splined and it should come right out after removing the rest of the bolts for the lower unit. I'm trying to lower the unit to replace the impeller by the way. Well, after removing the bolts holding the lower unit on, the lower unit will drop about 1 1/2 to 3 inches. It seems like the the only thing holding this lower unit on is the shift shaft running down the forward side of the motor. There is a small opening about half way up the motor on the front where the shaft is exposed. Looks like it's threaded together there. I have put the shifter in forward, neutral, and reverse and still no luck with this thing coming out. I have also tried to get an owners manual with an illustrated parts break down etc. on this motor but I cant find any for a 2008 model. Can somebody with newer outboard experience please help? Thanks a bunch and greatly appreciated 
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