the 578 was the last of the 5xx series, the 580 is a rehoused 630- even supports the full range of expansion options. Unless you're interested in a MAJOR undertaking, converting the 580 to trinitron looks to be near impossile as the analog board is unique to it, as is the new harness assembly to accommodate the 630 card edge. In addition, the front case has the 2-dimensional curve for the shadow-mask crt, so this would have to be changed, but the 5xx series faceplate doesn't have the right lockign tabs to accommodate the 580's chassis assembly.