http://support.apple.com/kb/TA34941

Question #8, pertains to 7500/8500

http://support.apple.com/kb/TA33978

Question #13, PM 9500

http://support.apple.com/kb/TA34662

Question #11, PM 7200

http://support.apple.com/kb/TA31863

Pertaining to x100 systems using the PDS video card

The reason I remember B/W on my PM 6500 is that I was really remembering it on my PM 6100 (both ran OS 8.6 at the time). I used HDI-45 video so that's how I got the extra choices.

Unfortunately you just need a very old Mac to run programs at less than 256 colors.