The parts I changed are the transistors (2 pcs, germanium, same type, NTE102A works IIRC). Notes I found on the 'net suggest C2 failure is a common problem. The Z tach is a copy of a Smith design used in some of the British cars.

http://www.classictiger.com/techtips/motach.html

Perfect. I will gather all the parts so that I'm ready to rebuild mine.

Thank You