I would suggest replacing the cylinders. I just did this on my 61. I'm glad I did because the cylinders were very corroded on the inside at the bottom of the cylinders. They were very pitted and close to rupturing. Years of moisture contamination in the oil?

Got mine off eBay from Convertible Cylinder Direct. They offer free shipping. They work fine, quality seems good. The cylinder walls seem a little thinner than original, but they don't make things today like they did back then either. One issue I did have was the holes on the mounting brackets were too small. My OEM cylinders had rubber bushings in the holes that accept the mounting pins. In order to reuse the rubber bushings I had to drill the mounting holes a little bigger. I contacted the manufacturer about this and they were excellent about it. They were going to refund me or offer a discount for the inconvenience.