I ordered the Comp 522-16 seals, which are for a .530 guide and are probably only .600 wide with only the viton being on the top side of the seal (sounds like what you tried). My valve springs have a .730 ID and my shims are .640 ID so I was trying to get something that would allow me to take shims on and off without removing the seals. My guides are all over the place because the .530 was so close to the size of the valve guide, the remaining support is breaking away (picture above). I have one cylinder left to do and I have 2 of the teflon seals left but I checked my math this morning and I probably have two shim stacks I need to change so I will have to remove the seal to do that and hopefully I can get them off without tearing them up. I was hopeful that as a back up I could use the vitons with a little black rtv sealer on them to keep them in place.