Are you talking about the self contained newer generation Sun tachometer or the older ones that require a dedicated sending unit.
Unless you're talking about one of the old black ones from the the late '40's, I'm not sure that having one rebuilt would be less expensive than just buying a good functional used one. There are so many out there for sale cheap. Just to make a point, I have a 1960's 8.5K rpm one on my shelf that appears functional that you can have for $15. But, maybe you have a special attachment to the one you have. Just a thought.
The Jalopy Journal
