Lothar, I think I once read that there are/were 74 holes in the AD firewall from the factory. Many are not used. Some are to hold the carpet/mat, some for the deluxe heater and the rest.....! That is one reason the cabs are always warm.
Bill


1949 Chevy 1/2-Ton
"Sedgewick"
In the Gallery
1989 Caprice