OK, let me first say that these things are extremely NICE!!!
I just installed my hubs today and they went on very easy.
Basic install: pull your old hubs, and put the 2 supplied spacers on your spindles, then pack the bearings with grease and install them into the hubs and bolt them on your spindles.
I will say for the money, it is nice being able to run my honda pattern wheels now, shame yamaha didn't use that pattern to begin with. Now I have new wheels and tires I can't use.