Classic air

No additional holes are required to drill except for the plastic fan motor blanking hole cover and the heater box support brackets. I installed threaded rivets in the factory fan holes on the firewall and drilled the plastic cover to accept the bolts in the factory hole location. The instructions say drill sheet metal screws into the firewall.

The original heater box is removed and the Classic Air box is mounted with the A/C lines going through the old fan motor hole in the firewall.