the real answer is actually very simple.
I used to be an NIASE certified mechanic at our local Chevy Dealership and I can tell you that brand new cars DON'T smell good..
when they come off the truck, they smell like welding slag and burnt grease.. much like the old factory where they were...
go to the YouTube link above to see Stacy David's TV Show "Trucks" in which he builds a "67-72 Chevy called Copperhead. and he gives you everything you'll need to know about building one of these models includeing answering the heater/AC question you originally asked.
as for value, ALL of...