Grab the drum and gently rock back and forth, and it should come off, unless you have one of those with the death grip on it.
When you finally get it off, you file a little bit in the egg-shaped hole, then you can test fit the weight/friction assy. onto the sleeve, no need to use the drum for test fitting.
With some of my CC kits, out of the box, you could tilt the bike to the side and the weight/friction assy. would practically fall off into your waiting hand, but of course, due to tolerances and quality control, the fit amongst the parts between various kits will vary greatly from loose to super tight.
When reinstalling the drum, use a turning motion so that the sprag roller bearings find their way into position on the sleeve, and keep your finger on the sprag roller bearing keeper. If you just shove it on, you will see the sprag roller bearing keeper start to lift up, and the bearings might fall out of position, but hopefully the thick Chinese grease will hold them in place.
Once you do it a few times, taking it off and putting it on, you will become more and more comfortable with servicing your CC.
Sometimes things are hard to explain using words, just go ahead and take a look at it, everything should become clear.
