My old 64 never had a heater in it, didn't have air in it either.

I am putting a 283 small block in it and I would LOVE to have a heater and air, all tucked away in the dash.

What am I looking at having to do so it looks like it belongs there?

I am NOT a fan of stuff hanging under the dash and I would not care if I had to remove the ash tray so something could take its place.