I haven't tried this with the EC yet, because I don't want to change the mouse feet. However, I think it will be useful, considering the wheel in the AM and FK are the same. It should fix the EC scroll wheel.
There are two springs that will likely varying in strength. Find the one that feels best and use it for scrolling down.
The clear plastic piece, with the indents, can be lubricated to smoothen out the feel. Use a lubricant that is safe for plastic. Make sure not to get lubricant inside the area the shaft goes into because the lubricant will prevent the shaft from fulling seating.
To fix the issue with the scroll wheel, use some medium thick tape, wrap it around the rear leg. Cut the tape so it is cleanly wrapped and to the length of the mold. Do not go to thick, you risk breaking something, use just enough to make the clip "stick" inside the mold via the pressure of the tape.
When assembling the shaft into the wheel you can remove any gap / play between the wheel assembly and the mold. Do this by not pressing it all the way in. Careful! You need to leave some room for when you press the scroll wheel button, if you do not, you could break the shell.
Before placing the wheel back into the mouse you may want to lubricate the contact areas of the wheel and shell.Edited by popups - 2/23/13 at 2:07am