I am trying to eliminate the shakes I am getting mostly in my shift stick.

I have just replaced my transmission mount, the passenger side motor mount, the two lower alternator bushings. The stick shift vibrates much less, but still a little bit (not too worried about that).

Now I am still left with a major problem as I see it, which is that the stick shift moves a lot when the road or pavement is not good, that is the stick shift seems to follow very closely road conditions! I still have to replace the driver side motor mount, I doubt it will solve that issue.

What causes the stick shift to move so much when roads are bad?

My suspension front and rear?
Some other bushings?

Thanks for your input.

Background:

-- The car is properly tuned and maintained, in the last 5K miles:

TB, IAC, flame arrestor were cleaned;
flame trap, O2 sensor, plugs, wires, distributor cap and rotor replaced;
wheels balanced, new tires + front alignment;
all fluids changed including engine oil, coolant, brake fluid, transmission (overfilled), rear differential, power steering;
new air, oil, fuel filters;
new airbox and coolant thermostats;
new mufler and pipes after cat converter to back;
new brake pads in front;
--
'89 244DL M47 161K miles