So an additional data point.
I ran 255 40 17 and 245 40 17 for years on my 65.
I needed to buy tires and I bought 245 40 17 and 235 40 17 because they were the only size available in the brand/tread I wanted at the time.
I haven't even put 500 miles on them I am already tire shopping.
The smaller side wall from the old set to the new set plus I suppose the tread change....road noise, vibrations, overall feel of the car sucks. I've convinced myself it will feel better if I go to a 245 45 17 and a 235 45 17....the car will also look better with the taller tires again. I should have saved my money and waited.