68 Charger A/C Question - Heat out of the right vents, but not out of the left?

[Corellian Corvette]

Simple question that hopefully has a simple answer.

When I turn on the heat (or defrost for that matter) on my 68 Charger with Factory A/C, I get heat coming out of the RIGHT (passenger side) vents, but not out of the LEFT (drivers side) vents - the air out of the right side is warm and left side is cold. Now the Air Conditioning unit was rebuilt by Classic Auto Air, and all other functions appear to be working correctly. My cursory view of the Service Manual does not show me how airflow is distributed side-to-side.

Please tell me this is something simple like one of my vacuum hoses is routed improperly...

Thanks!

[Rolling_Thunder]

From what  I remember the dash vents are fed via a center plenum (located under the radio) - there is a vent hose running to either side of the dash - maybe yours got disconnected somehow? There should be a molded plastic piece that also runs from the plenum to the driver side flex hose...       double check them - make sure there are no holes, tears, or disconnected.