Okay everyone, I need a little clarification on something. I have a 1976 r90/6 US version and just got new bullhorns to replace my old ones. On my old ones, I see that there is a (what looks like hard plastic, but may be rubber) sleeve between my carb and the bullhorn. They are also old, so I was going to order new ones. I see from the parts diagrams that it looks like this sleeve goes on the other end of the horn against my air intake box. Do I have this part on wrong? I even looked up the boxer2valve video and he installs it up at the air box. I've seen another 1976 r90/6 with it installed the way I have it. Any ideas? I believe the part number for the sleeve is 13 72 1 257 395. Thanks!