I finally picked up a CLS2000 color head. The main reason I wanted it is because I wanted better evenness of illumination, compared to a coldlight.
I was going to do a complete rebuild and restoration, but the unit I picked up was in very good shape. Thanks to the air filters on the back, the innards were pretty clean. The dichroic filters were also clean.
Before plugging it in, I inspected every connection and every circuit board. I did find that the shutter looked to be rigged 'always open' and there was a big burn mark on the shutter motor printed circuit board.