Jerry rigged wiring

Sorry - I have shrink tubing all over the place. Will try.

Maybe this helps. I have three connections on -, two on +. And a Crack. Mind that I moved the coil down.
On -, one must go to the ecu (via upper harness, bullet connector) and one to the tacho (spiral blue on white). On + probably the power, white. But I don’t know for certain; maybe I made a picture I can find.