Oh well, so much for that. Another possibility is to duplicate 2230 ROMs and try in a 2220.
As I mentioned, the purpose of the big X could be to align the storage display with the CRT. The lines should cross at the center, and the slopes should be to confirm linearity and set them to cross the CRT graticule lines at the intersections all the way to the corners. These adjustments are in the vector generator, as I recall. There would be offset and gain adjustment for vertical and horizontal. Maybe it's a factory setting not normally accessible to the user.
If the X isn't for that, then there may be something in the diagnostic menu to draw some kind of pattern for this purpose. There should be something in the service manual about this alignment process.
Ed
