GE 14T009 Restoration

[Mre12ax7]

Hello,
I have been working on this GE for the past few weeks but am having a few issues.
So far I have replaced all the old paper and electrolytic capacitors, selenium rectifier , video detector diode and the AFC diodes.
Which has got me to this.
IMG_0235.JPG
As you can see it has horizontal and vertical lock but the horizontal jitters and does not lock in the right place. Sometimes though I can get it to lock correctly (not in picture) but it then goes to this.
IMG_0236.JPG
The picture is now very dim and shrunken in and no controls will bring it back to before, it must be turned off and then turned back on again to make it go back to normal.
This also happens when you mess with the horizontal hold control too much.
My longtime friend at the last radio/tv shop in town has suggested that the flyback is bad.
Does this seem correct? Or should I try different diodes for the AFC (I used 1N4007's).
I really would like to see this work as it is my first TV (I have done many radios).