I hope this works, but here are some pics of my os18 tztx with the cvrm 18 cooling head. First off, the header should have some type of cooling. My header is associated 'factory' part that use to be blue, but not anymore due to the heat. The heat also melted some of the pullstart handle and pull start case.
I shaved off the area between the head button and the case since with the tz, the sleeve is almost flush with the engine case. In order for the button to have better contact with the sleeve, I shaved of the extra metal between the head button and the case. In the picture, I pointed to the area that I shaved almost all the way down. I also used longer head screws...the screw heads were larger than stock, so I had to open the are on the black part where the screw comes down in the head so it can seat properly. I didn't what the screws sticking out on top. At the end, the head screws were flush with the top.
this is what I did. Hope this can give others an idea of what you should or should not do.
