Thank you so much for the responses.

I pulled the instrument panel today and disassembled the tach. I could not find any burned traces on the board. So I put it back in and the tach and glow plug indicator light still do not work. I discovered that the clock only works when the car is off .

I came across another thread who had the same problem but in a w201 car and lost his cruise control. My cruise control hasn't worked in a while and I have no intentions on fixing it but it made me wonder if the problem lies somewhere other that the instruments themselves.

I have no problem replacing the tach and clock (I will replace my temp sensor LCD while I'm at it) My consern is that putting a new tach and clock in will not fix my problem

If anyone has any comments, I would greatly appreciate them.

BTW, disconnecting and reconnecting my speedometer cable made my needle stop jumping at low speeds