I had to replace a dammaged tire so I pulled the rear wheel off last night (first time) it was difficult to get the caliper past the wheel. I am going to remove the pads from caliper to make more room. There was a rubber duhicky that came out of the caliper mount. How does this go back in? and at what point of the procedure? Any other tricks? I was going to replace the axle shaft in the opposit direction with the nut on the exhaust side, any reason not to do this? Does the shaft need lube?