This dash panel will be using a Vintage Air (refered to as "VA" from now on) controller to operate the VA AC and Heat/defrost system. If you are using a stock heater control panel, mark the opening on the posterboard, cut, and then transfer to plastic and cut. If you are using a VA controller you will need to find the centerline of the original heater control panel by measuring on the posterboard and drawing a line. The line is used as a guide to keep the VA controller straight when deciding where you would like the VA controller positioned. Keep in mind that the circuit board assembly on the back is larger than the face plate and you have to keep the whole assembly high enough on the facia to provide clearance for the circuit board.
Once you've decided where to mount the VA controller place the face plate on the posterboard and mark the opening. Cut the opening on the small side and then sand the cardboard to an interference fit. It is important to the finished product that the hole for the face plate be exact. If the hole is too big the face plate may be able to slide around in the hole because of the way the face VA assembly sandwiches the facia to hold it in place. Once you have the VA controller opening where you'd like it, place the posterboard on the plastic panel and then repeat the process on the plastic.
Vintage Air provides a template in their instructions for people installing their controllers in places where the template would make it easier to locate the face plate. For this installation I would recommend not to use the template but rather just trace the actual face plate where it fits in the facia..
