1967 GTO ac vacuum actuator install help
 

What is the sequence of steps to remove an underhood ac vacuum actuator from a 1967 GTO and to install a replacement ?Neither the 67 shop manual nor P. Zazarine's resto guide have any instructions.
It looks as if the whole plenum box will have to come out which might entail removing the inner fender liner. If anyone has done this before, I'd appreciate your guidance. Thanks!

It's a PITA, yes you have to remove the case from the firewall.
You might be able to reach the 2 speed nuts by taking the blower out but that too would be a PITA with the case still mounted.