Hot Rods Model A banger Sun tach and sending unit wiring info

I found a NOS Sun 0-4k tach Model RC 40 and recently acquired a EB-5A sending unit for it. The tach says use with Model EB sending unit. The transmitter is marked 6 volt, 4 cylinder. (the 4 terminals are marked GRD, DIST, +, - . I want to use this on my Model A banger. Does anyone have any wiring info for this setup ? I don't want to do it wrong and smoke something. I am still running the stock distributor and negative ground.

 

You open it up and see if the batteries have corroded?

 

The sending unit looks unused to me. That raise the question, what kind of battery goes in there, a AA ??