AC system update

Can you not use a factory A body AC duct?

They sure look like they could be adapted.

I adapted the factory ‘69 A/C vent box to my Classic Auto air system.

It wasn’t too difficult. Just had to cut the hose ends off the supplied ducts and manufacture an aluminum plate with 3 oval holes to bolt the supplied duct hose ends to then to the factory A/C vents after they were removed from the factory vent box.