I recently read about the 580 on wikipedia:

"Lastly, the Trinitron display of the 575 was replaced with a cheaper shadow mask screen, causing a slight change in the plastic case surrounding the CRT"

From that quote I'm led to believe you might have problems getting a Trinitron CRT to mount correctly in a 575 case. It might not be appearent on the outside. It could be a change in the interior with how it mounts to the plastic. I've personally never own either machine though. I suppose you already decided it's worth the risk.