New thought on this...

How 'bout running the X server in a lower bit depth (like, say, 2 or
4)?

Is there even an appropriate flag or Xresource to pass to Xmacppc to
get it to do this, or is it bound to 16 (8?) bits?

(It'd be nice if Xmacppc had a man page. As near as I can tell, none
of the port-specific X servers have a man page, but uniformity isn't
inherently a good thing.)

Guess I'll go see if there're any leads already in the FAQ, then
break down and dig through Xmacppc's source.

::sigh::

-- 
       ~ g r @ eclipsed.net