Drive gear vibration?

The bolts he's talking about hold the flex plate to the torque converter; they're accessed by removing the metal inspection cover from the lower portion of the bellhousing. But if they loosen, they will tend to make alarming noises, not cause the vibration you're talking about. They are not causing your present problem. First, get the books described in this thread. All three of them. Then, do a valve adjustment and follow the tune-up parts and technique suggestions in this thread. You will likely also need to pay attention to the carburetor; Carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted here for free download.