I know, I tried. If you go further past the 22Khz mark, it causes lots of linearity issues in the horizontal. Thats leaving the circuit stock with no changes. 

The vertical circuit, no problem! Horizontal, Nope. 

However, I was able to get grayscale from the original video amp circuit, even though technically its not supposed to. Just couldnt increase the resolution. This is of course with the logic gate out of circuit (cant greyscale through a digital gate). With an inverting unity gain op-amp.