One of the e-clips looks like it's bent. Try to flatten it out if possible.
The clips go into the groves on the gear holders. Your best bet is to make sure the gear is pressed on all the way so you can see a slight lip at the edge, then snap the clips on. It is 10000% easier to get those clips on if you have an external snap ring tool. You can pick up a set at your local auto parts store, Lowes, HOme Depot, Sears etc for under $12, It works much better than trying to use needle nose pliers (although in a pinch they will work too)
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