Power Brake Hose Check Valve ('65 Formula S)?

Update to post #1: I just completed some more research conducted in reading the 1965 factory Plymouth parts catalog/manual. The blow-up photo of the Valiant/Dart power booster shows the vacuum tank and hose but no check-valve. Looking at the parts list, there is a part number for the vacuum tank but no part number for a check-valve for the Dart/Valiant.

Now, it is just the opposite for the larger Plymouth/Imperial line of cars. There is no vacuum tank listed at all, but there is a part number for a check valve.

Now I begin to see what that "extra" vacuum tank is used for on the '65 Abody power brake vehicles: for whatever reason, Chrysler used the vacuum tank as a reserve, which in other larger models is taken care of by using the check valve in conjunction with the firewall booster itself. Why the difference in engineering is anybody's guess. In any case, I won't be needing a check-valve after all.