Air shocks will do the job. That said, many feel the upper mounts aren't strong enough, especially in a 50 year old car. They are a bit on the flimsy side, but just in case I modified mine by adding a 2x2 steel crossmember for strength. At a minimum check closely for cracks in the metal and repair them if you find any.
My 64 SF is a little short on tire clearance when accelerating hard or I have weight in the trunk.
I'm not ready to buy tires or rims at this time. I am considering a little help from air shocks or if necessary air bags. I am just touching enough to slightly show on the tire sidewall and I see spots on the inside if each fender on the undercoating. The springs were new about 8 years ago when we rebuilt the car.
I would appreciate any thought and suggestions.