I tried my best to convince him. I told him about the heater/defrost unit from Vintage Air that ariffle installed. I pointed out the fact that his car will have dash vents that won't have a function. - And I told him that now would be the time to do the installation while I'm working on the firewall.
He wants us to try to bring fresh air in through the cowl still but operate without a fan.
I guess I need to come up with more reasons before he'll give in.
The '68 Chevelle he used to own didn't have a heating system and he got by with it for several years. He used a dashtop ceramic heater whenever it got foggy inside.