I believe there are 8 different 1969 Mercury Cougar under dash harnesses (Ford number 14401).
There are early and late versions. Identified by the color of the plug, either white or black, which must match the printed circuit board of the instrument cluster. Red printed circuit boards go with white plugs, blue printed circuit boards go with black plugs.
XR7 (and Eliminator) is different than Standard model Cougars.
Additionally, all versions came with or without air conditioning.
I knew about the Quarter Horse Mustang, but not the Shelby's with Cougar dash.