Did the 1970 Cougar use a Heater Water Control Valve? (351C)

I've been restoring the factory A/C on my '70 convertible, and have made it almost to the finish line. The Classic Auto Air parts supplied to me to refurbish the system did not include a vacuum actuated heater water control. Based on the diagrams I've found on the Ford Parts Manual CD, it's difficult to tell whether the Cougar used it or not. In fact, a 1967 illustration even said "not for Cougar", which makes we wonder about the 1970 model year. Why would every other Mercury or Ford model seem to use it? Can anyone tell me definitively if it's used, and if so, where is the vacuum source? If anyone has a factory air '70 Mustang with a 351C, that should be close enough.

Thanks much!

Thanks, I found that exact link yesterday after going to a local parts house, and the guy behind the counter produced a valve both heater hoses are meant to run through. Not going to do it that way...