>
> Now what to do with the Hall unit +12v out.

Looking at the Bentley wiring diagram, I would assume that the hall unit to
ECU wire is there to tell the ECU how often to fire the injectors. The ECU
needs to know, and there's just the one wire between the two, so I reckon
it's a good bet.If the MegaSquirt is already tied in to the hall sender,
it's probably superfluous.

--
John Bange
'90 Vanagon - "Geldsauger"