Did all 428 SCJ Mustangs equipped with "W" code 4.30:1 rear end gears come with a DAPCO "Detroit Locker" differential?

Contrary to most published literature, documentation describing the Detroit Locker doesn't appear from Ford until approximately November 1969, which is well into the 1970 model year. Earlier documentation that I've seen, such as original invoices, clearly describes the "W" code differential as a "Traction-Lok" differential. This is an ongoing research area, and it would be very helpful if anyone who might have documentation describing an original Detroit Locker installation in a 1969 Mustang could share their insights. See the CJ vs. SCJ page for details.