I have a gamefisher 5hp model number 225587500. I was replacing the impeller. When I was pulling the impeller off the driveshaft came up a bit and sounded like something came loose in the housing. I looked inside with a flashlight and it looks like maybe the pinion gear is floating around. So I figured it was time to take the lower unit apart and fix. I got the propshaft cage retainer off - part 18 on this diagram. Now what? I dont wanna fudge anything else up. What do I remove next and how do I do it? Thanks.