How to run Heater after A/C deleted

85B27E6A-FAD5-4CD4-A04F-28F764892D0B.jpeg A6CC0FD1-87FE-4388-8CCC-5FD382222784.jpeg 1968 Dart factory A/C car. I removed the AC unit and lines but still have the original dash unit with push button vacuum controls.

Is there a simple way to still control the heater flaps without the funky vacuum canister that was originally on the fender apron? I circled it in red. What if I just hook the dash unit to an available intake manifold vacuum port? I’ve only had experience with non ac cars that were cable operated.

Thank you