Car: 1972 GS Stage 1 with Auto Trans and A/C. I have some holes in the firewall that I need some help understanding what they are for and if they need grommets. I have added some pictures to better describe my questions. 1) There is a small hole to the right of the voltage Regulator. What is this hole for? 2) There is a 1.75" hole to the right of the Blower Motor Relay. I believe this hole is for the wiring for the A/C controls in the dash, coming from the engine bay. I believe this hole uses the 1.75", single hole grommet. Can anyone confirm? 3) What is the square hole to the right of the throttle cable for? 4) Do I need the 3 hole (2.25" diameter) grommet that is used for A/C vacuum lines? If so, where does this grommet go? (I don't have any 2.25" holes in the firewall). Thanks in advance for your replies and knowledge!