On the exede harness what is the black wire next to the boost blue wire? and where does it go?

 

The ground?

 

Is there a terminal on the end? If so, what kind?

 

It goes into the yellow factory connector.

red/black pair second map (optional)
black long with the ring on the end = ground wire goes to 10mm nut that mounts stock ecu
boost wires blue/black with weird tips one needle male and one female. You pull the boost pin out of the factory ECU connector and put the male into it. The female goes back in where you took that lime green boost wire out.