I've read the thread on valve adjusting but I am clueless on where to put the feeler gauge? I know it should be rather simple. I see the ajusting screws and I had thought that I measure under the arm which is under the adjusting screw... but I don't see and/or feel any gap where any size gauge will work. Yes I don't have another person with me who has done it before at the moment. sorry for the noobish question but I sometimes need to be hand held and with pictures. Anyone else had this problem on their first valve adjustment?