So you're still tied to either daylight or tungsten and swapping or mixing tubes in the Diva's? .
Depends. The Quasar Crossfades are adjustable from 2-6k (IIRC), that’s what I built my conversion with (bought a bare 2’ 4-bank shell and went from there). You could also build one with the Rainbow RGBW tubes or simple/inexpensive single color tubes depending on your need.