I was running Shimano XT brakes with an XT shifter that used the I Spec mount so I pulled out the little shim/spacer piece on the brake. I have now switched to Box Components Shifter so I pulled the XT shifter off. Now my problem is I can't find the little shim/spacer to use when just using the brake alone and not with an I Spec shifter mount so I can't get it to tighten down on my handlebars. I have searched all over and can't find a source to find one. Any suggestions?