[DanMartin]

Not sure about anyone else, but my installation using a MSD-6 Digital box uses a tach adapter (MSD Part number 8920) to drive the Smiths gauge. Works fine, and no issues.

The digital MSD box even does the gauge "Sweep" on start-up (will show you where the limiter is set), and that works fine through the adapter. I believe it's a 4 wire install (power/ground/tach in/tach out).

Hope that helps.