Cut some 10x3mm aluminium flat bar and riveted to the bottom edge of the panel back to stiffen it up and help carry the load of the panel.
Added some 25x25x1.6 angle to the centre console support to prevent kinking and then a piece of 50x50x1.6mm angle which will have a piece of foam on the top surface to reduce the levering action from the weight and depth of the radio.
Installed the choke, throttle, carb heat & cabin heat cables to the panel.
Under the bottom edge of the panel back, you can just see the flat bar riveted on