[Spits] Mail-in rebuilders for late-model tach?

[s1500 at comcast.net]

You know, in the last days of when I was driving my Spit for this year, a shred of hope happened for my tachometer.

Ever since I converted to a different ignition module(the original Lucas one conked out), my tach never read right. Despite adding in a resistor, replacing wires, etc, it never read right. It always seemed to be at half of what it should be. Then often when I slowed down(ie rpms down), it would bounce up. That would be the only time it ever read past 1500.

But lately, when I drove it, typically over slow & slightly bumpy areas, the tach read correct! I'm convinced there's some slightly loose connection in tach itself that needs to be rebuilt/reconnected & I'm good to go again.

Is there any place I can mail off my tach over the winter, have it rebuilt(for less than the cost of a new one) & have it back by spring?