I was working on this car for my neighbor, it has been sittng for years and I replaced the fuel pump and got it started, but I noticed there is a gromet on the top of the air cleaner and it looks like whatever was supposed to be there is gone. (can be seen in this picture) http://i735.photobucket.com/albums/ww351/mercedesbenz911_photos/Parts%202/1595dd15.jpg

What is supposed to go there?