The biggest problem you will have is finding the original firewall insulation plug that took the place of the heater motor. The fresh air vent is right side only with the door hinged on the right side of the vent, and there are two black pieces of cardboard type material that cover the holes in the dash under the speaker grill where the defroster ducts came thru. Early Falcons share many of the same delete parts. The dash control and firewall plate are reproduced. The plugs that seal the heater hose holes push thru from inside the car. On the engine ford simply capped the water pump and intake connection with a plug and a hose clamp. You are better off installing pipe plugs.
I tap and install Allen plugs in the factory fittings and THEN
cap those with the factory rubber cap and factory clamp. That gives the vintage look but also the security of not having to worry about the rubber plugs failing. PM me, I have a heater delete set up I a not using that you can talk me out of