just a note: if any one needs a Beveled Washer, look here. this would work for the top and they are made of super hard rubber and should work great. I know they make a teflon one to an any size but Ill have to look for it.
just a bit of info that might help some one out they also make Beveled metal grommets too will look for likes
http://plumbing.hardwarestore.com/51...t-washers.aspx
http://tbn0.google.com/images?q=tbn:...es.com/catalog
http://sth2.com/Z-car/cone-washer.jpg
google Cone Washer