It should just slide back on in line with the key. When you put the slide back on the end of the shaft and tighten the bolt to torque it, should be set. Do this first without putting the stator cover on and make sure the starter gear still turns one way. The first time I did mine, for some reason the starter gear wouldnt move at all. I was trying to start it and chewed the starter. Maybe I over torqued it? Who knows, I used a torque wrench. Anywho, just make sure when it's torqued to specs that the starter gears do move freely.