Today I got the new BUNA-N O-rings to repair the convertible top cylinders. I have a bunch of the VITON too so if these fail I got it covered. The assembly consists of a snap ring, followed by a wiper cup, the felt wiper, a steel washer that forms the bottom of the wiper cup, a plastic washer, and finally, the O-ring. I took the opportunity to polish the ram shaft with some 400 grit wet/dry paper and a few drops of ATF. They both came out nice and smooth and shiny. Then I cleaned them up with some spray carburetor cleaner to get all the crud off the parts and clean out the cavity where the O-ring resides. Then I wiped down the outer cylinder to get 50 years of grime off. Getting the O-ring over the end of the ram was the hardest part. It helped to secure the end of the ram in the bench vise so you can use two hands to stretch the o-ring over the big fat end. After that it slipped over the other parts pretty easy. I lubed it all with a few drops of ATF so it all slipped into place. The snap ring was as difficult to get on as it was to get off. The fat part with the hole doesn't fit between the cylinder and the shaft. Again the vise helps to hold it steady while you fight the snap ring. The snap ring pliers could not get the ring into the groove. I used an awl and a tiny hammer to persuade it into place. Once seated, everything feels good. If you hold a finger over one of the hose connection holes and work the ram, pressure and vacuum builds and I don't hear any air leaks at the O-ring. So far so good. Next is to hook it all up to the pump and test for leaks. I will build the bleeder tool that is explained in the fisher body manual. This is the parts order, snap ring ,and finished cylinders.