Vintage Cars: Vibrates and No Tach, steering damper, steering linkage

Question
Ron:

On my 1983 merz 300D at about 65mph and above the car vibrates?  It is not the tires.  It does not change when you steer side to side?  The whole car has this vibration?

Tach works only part of the time, any ideas?

Answer
vibration at speed is normally tires, are you sure they are balanced properly?
If they are and alignment is good then you could have a variety of other items that need checked.  Steering linkage, steering damper and trailing arm bushings.
Getting it up on a rack is sometimes the best way to evaluate the integrity of the front end.
Tach - electronic , can be tach or sender.You can pull the dash pod and check connections for integrity
Good Luck