What was the purpose of the large slot cut out on the passanger side under the cawl? I removed the part looks like some kind of vacuum valve but im not sure.

That's the upper vacuum actuator for the A/C air inlet adapter - there's another one behind the RH kickpad. When the upper valve was open and the lower one was closed, the A/C system took in outside air ("normal" position). When the upper one was closed and the lower one was open, the A/C system operated only on recirculated inside air ("max" position). :thumbsup:

Well, I have all part's exept compressor. Thanks for the reply, what good books could I get that would show how it's run from wiring and hoses

Well, I have all part's exept compressor. Thanks for the reply, what good books could I get that would show how it's run from wiring and hoses

You need the '68 Camaro Assembly Manual - all the usual vendors have it. :thumbsup: