1977 Southwind 18 motor mounts

Joel,
Knowing more about what engine and mounts you have will help but it sounds like your rubber mounts are in need of replacing. If this is true, here's a source of some rubber replacements. Also if true, I doubt the prop shaft is where it "needs to be" I highly recommend not running the boat until the rubber mounts are replaced and a complete engine and shaft alignment is performed. Post some pictures. Please be aware that if you run the boat with bad alignment, it can and most likely will cause damage to other components like the cutlass bearing, prop shaft, shaft trans coupling shaft log and even possibly transmission damage.