The o-ring that seals your bearing plate to your axle tube is plain not gonna stay in place without some help. The bearing needs to be lightly tapped on the axle, so apply some rtv of choice just to hold it in place while you position your bearing.
Here is the bearing plate, caliper bracket, and line bracket mocked up:
Here's another issue with this kit. The turn cam that drives the caliper closed is dry, I think it needs grease. Rotate it out of the caliper, add the grease/lube of your choice and re-insert. Also, the long bracket needs two things done, remove the powder coat out of the hex hole at the bottom, and two: remove the powder coat out of the slots, otherwise this will not go together. Hey at least the tolerances are nice and tight.
Threw the disc and caliper rear bracket on after the touches: Another issue, focus on the castle nut. They supply you a very thin washer, well its not thick enough. You will need to add 1/4" minimum in washer thickness or the disc will slight left and right because the castle nut runs out of threads before its tight. I put their wider washer first, then my thicker one next, then the castle and it worked perfect.
And this is fully assembled and adjusted. Huge improvement.
My driving impressions were: Good stopping power. If this was your only brake on the machine you could get by easily. I'd say it stops as good as a perfectly functioning drum setup, the difference is, this wont hold water and stop working. Should be easier/cheaper maintenance and upkeep also. Win/win.
EDIT: Added hydraulic to it.
I started by buying the generic 68" ATV brake cable off ebay. It was about $20. Anything longer then that and price goes up quite a bit and is hard to find. Turns out the stock brake line is about 80". So yeah, it didn't work. Here's what I had going for me: $24 generic driver side master, revised bracket, new caliper/pads:
Came up slightly short:
Turns out for "scooters" there is a longer cable for about $30. Well before I knew about that I bought an AN line from Russel. I converted the brake fittings to AN, used straight couplers, and a prefit, pre-made brake line so it was all plug and play. Perfect fit, and remember I have the 2.5" longer 450 swingarm. I bought solid washers also instead of the oring stuff that SuperATV provided.
I was even able to keep my winch control on the drivers side:
Impressions: Stops incredible after about 3 pumps. I think the master is not strong enough to make this caliper do the full amount of work its capable of. On the first pump its a decent braking amount but not enough for an emergency move...by the third pump, its got impressive stopping power. I may change to a name brand master and see if that makes it better.