[Hughes]

Just to cover myself.
I need to know the location of the ECU on a 2011 Z6. My manual showa a picture of the ECU mounted to the frame... But no identifying location points.
I ALSO need to know the color location of the wires attached to or on the connector plugging into the 4 pin connector on the Fuel Pump.
My machine came with a jumper of mismatched colors with a 4 pin connector at the fuel pump and bare pins which plugged into the 2 pin connector coming from the Fuel Pump Relay.
They FELL out.

[NMKawierider]

I think the first Z8s were like the Z6s in that the ECUs are mounted on the driver's side on top of the frame in line with the steering wheel. I have a video in the How To section showing the Z8's location so people can delete the reverse limiter. As for the rest...you have the manual and the wiring diagram. Good luck.

[Hughes]

Unfortunately the manual was just short of useless...But
I managed to get ahold of a dealer in WVA, Louisville and Lexington are CLOSED on Monday.
The dealer was able to find a similar unit with a Red/Blue cable and identify the BLUE wire as the ground side. I matched Blue to Green  and put the RED to the other pin and now It is wired back correctly. And I taped the pins with self bonding tape so it won't come loose again. Unfortunately that relay doesn't work, due to a missing/failed command line from the ECU. I verified the relay by simply removing it and shorting the contacts and then listening to the Fuel pump start to hum.
You are right about the ECU.. It is mounted under the dash on the drivers side. I cleaned all of the contacts with DeOxit but it didn't fix the Fuel pump.
I guess next is to remove the ECU, open it and see what kind of damage it has. That should be fun. At least I understand Electronics.