I have the Cybervision 64 not the CVPPC, although I would like to find one.
I guess I am a RTG dummy but from what I am gathering, I would be better using the PIV as that would be a 1 monitor solution correct? If I understand right I could use either the CV64 (or CVPPC for that matter) or the Retina Z3 and the Indivision together but would still have to use 2 monitors or a LCD TV with 2 inputs correct?
I suggest you take a look at your CV64 and also read the manual.
The CV64 has two VGA connectors behind it. One is the input, one is the output. You connect the indivision to the input port and your monitor to the output port and get a single screen setup that autoswitches when you change between custom screen modes and RTG modes.
The CVPPC has no passthrough (external monitor switcher needed) but is a faster card than the CV64 or the PIV.