Like many others I have found it difficult to remove and, in particular, reattach the air filters because it is difficult to reach the screw with the filter in place. I have seen that some forum members have replaced the screw with a stud with a hole drilled through it, and a wave-type cotter pin through the hole to hold the filter in place. I had some difficulties in getting that connection firm and air tight, so instead I used studs that I screwed into the threaded holes in the filter, and used nuts on the carb side. It was much easier getting nuts on the studs than using the original setup with bolts.