You didn,t say what year you have but your profile says 56. Jack the rear of the engine up a little & replace the upper mounts. The bolts are 1/2 in. coarse threads but i don,t know the length off hand. They originally come with a lock tab but I generally use a flat washer & lock washer. There is a sleeve that fits over the lower part of the bolt. If it or they are missing you will have to get them from a specialty supplier. They can supply the bolts too. You usually have to stick a tappered punch up in the hole to get the upper mount in position.
