Not sure if this helps, but these are pics from my 66'....Everything (AC/Heater ) works !To be more specific I need to know how to route the 1/8" vacuum lines that come through the firewall in the upper part of the heater box. Anybody have a similar car that you can send me some photos?
Attached is a photo I found on line to clarify which lines.
Thanks for the info, pictures and drawings. On these cars does removal of the air box/case include removal of the fender like my '69 Camaro?That is without question the wrong actuator. All '66 AC equipped A-Bodies utilized the plastic two port unit.
These are avail from most major Pontiac vendors, However the air box/case will need to be removed for installation.
Attached below are the Vacuum Diagrams from the 1966 Tempest Air Conditioning Manual.
If I can can assist further with anything from the manual just let me know.
I'm working on a '67 model and see it is represented for '65 - '67. https://www.opgi.com/gto/1967/interior-accessories/heater-ac/BR02521/ I'll have to place my order.....I agree with GTOJUNIOR, that the one in your picture is incorrect. ...I looked up the correct one for the 66', in the Original Parts Group Catalogue and it's Part # BR02521...$88.00...Maybe a better price somewhere else, but ....... My Best J