1- vibration: Could be the exhaust (check the bracket holding it to the bellhousing), or could it be the fan (I assume you have the visco fan, not the fixed one?) just thwapping into something?

2- if you haven't done so a good tuneup is always nice. Is this vehicle FI or carburetted? For FI check the throttle body and aux air valve.

3- All the balljoints are supposed to be held into place with little wire clips, looks like a C with one of the ends extended and bent at right angles to the plane of the C (makes sense? From the side it would look like an L). That extended thingy goes through the tiny hole in the socket and sits in the hole on the opposite side, the C then turn and clamps onto the rod. The important part is that there's something going through that hole to hold the ball into the socket. I've bent plenty of these from paper clips, previous owners tend to lose them for some reason. Alternatively, hold the ball&socket together with a strategically placed tiewrap.

Bram