Here's another view of the new levelling intermediate plate. It works too!
The only thing that I had to do after this was grind down and drill out some big nuts to make bevelled washers. They were necessary so that the nuts that bolt down the carburetor could clamp to a nice flat surface, insted of having an angled surface to push on.
I have had exactly zero problems with the car stalling under braking or acceleration since I made this modification.
