I just picked up the strobe slipper for my E-Maxx. I put the spur gear on and got everything else ready. I went to slide the strobe slipper on and the bearing didnt fit. I just used the little spacer thing off the stock slipper in place of the bearing.
The Strobe will wear out if you use the stock bushing. Get a file and file the hex a little on each corner(on the input shaft) so the bearing slides over it. It takes about a minute to do with a file.