Using the notes mbear2k posted, I was able to completely eliminate the retrace lines
I also put a scope on the horizontal output tube's grid and saw this.
There's some ringing in the waveform that most likely accounts for the vertical bars on the left.
The signal at the preceding stage (horizontal oscillator) looks correct so I'm not sure where it's coming from.
Otherwise, the set is playing fine, just a little dim and washed out. I may try rejuvinating the picture tube
