I'm working on a Mr. Do board and have it working, mostly. After changing 4 bad 74LS161 counters and 3 bad 74LS74 flip flops and 1 bad 74LS107 flip flop, I finally have a working board except the screen is curling on the left side. I'm positive it is not the screen. In the images you can see the Mr. Do board curls on both LCD and CRT monitors, while a bowling game works on both. (yes, there is a slight curl on the crt, but not Mr. Do curl).
I have checked the counters again and the sync signals and all seem w/in spec. Any guidance and where to look now? Thank you.
First 2 images are LCD comparisons while 2nd 2 are CRT.

I have checked the counters again and the sync signals and all seem w/in spec. Any guidance and where to look now? Thank you.
First 2 images are LCD comparisons while 2nd 2 are CRT.

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