Hunting for picture of unmolested B series firewall

Working on a '59 BD-162. Previous owner hacked in what I believe to be a D-series heater box and heater core enclosure, and carved a large hole in the firewall for this. Battery was moved to the front driver's side inner fender. I found a firewall mounted battery tray and under dash heater box from an A series that I will be installing in there. As I need to patch up that large hole in the firewall, I figured this would be a good time to also patch up any other holes that have been added over the years. I'm attempting to return the truck as close to stock as I can, or at least using period correct parts.

I've been trying to find a clear picture of what would have been there hole wise on the B-series firewall from the factory, without much luck. Can anyone help, or even just a diagram of what should be there?