On the way to repairing something else, the underhood vacuum actuator on my 67 GTO convertible got broken/damaged. Old plastic,thick thumble thumbs and "uh oh" don't mix. The upshot of this is that I purchased a replacement vacuum actuator from Ames and set about replacing it. Which is as far as I've gotten today. The vacuum actuator is mounted on the heater fan box and plastic ducting under the hood on the passenger's side. It looks as if the only way to get to this part is to dismount the fan blower housing and connected plastic ducting ,take it out and replace the part. Which, because of all the ac parts being on the same side ,looks as if the inner fender liner will have to come out. I've looked at the comments about this on our board because the 66 & 67 Skylark ac vacuum actuator setup is very similar to the GTO. If anyone has made this same repair before, I'd appreciate your guidance on the how-to and step sequence involved in making this r & r. Just another comment/observation. Why oh why did GM engineers mount the blower fan motor upside down at the back under this assembly? How many of these GM A-bodies which have had a fan motor/squirrel cage replaced are running around missing the screw on the fan housing closest to the firewall? Or have a round hole in the inner fender where a cut out metal circle has dumdum seam sealer to hold it in place where the inner fender was cut for access. Thanks y'all. I don't want to make any mistakes that I could avoid, so I'd appreciate advice from anybody who has done this before.