After several tries, I was able to fit seven 8×8 matrix side-by-side on a breadboard and not have wires crossing over the displays. The key is to put the chips on one side (rather than above or below) the matrices. You can put another 7 driver chips on the right side and double this to a fourteen 8×8 side-by-side matrix!!!
By customizing the breadboard, I was able to rearrange where the power buses are and use them not for power, but to have a common bus for the eight anode rows shared by all displays.
Considering each display require only 16 wires, I was surprised how much time this took to wire up. One thing I learned from this project is that I should not be so stubborn in using the correct wire colors. I ran out of wire of correct length and color and that allowed me to work faster.
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