This is a replacement for an alternate solenoid found occasionally on 1969-70 Cougars
and Mustangs. An original will have a Ford part number stamped in the base. The
installation is documented in the 1970 Electrical assembly manual, Page EO-115-1.
I have one from a 1969 Cougar 351, marked C7AF-11450-A3, date code 9AC. These are
highly prized by Mustang folks who believe they only came on 428CJ and B302 cars.
No such designation is made in the manual.