I let the car sit for 2 weeks then since I started using it again the
tachometer has been erratic, zero then on target then sometimes
pegging.  It sometimes moves when the engine isn't running.

Searching the web it sounds like I need a new instrument cluster.
Anyone ever see this condition with anything less than a bad tach?
I've taken the instrument cluster out and gone over the plug
connections with a lead/graphite pencil improving the contact but no
improvement in tach behavior.

Bill