Yamaha CS80

I believe the Kenton mods are strictly midi and in this case don't give you 
anything but note in at least on the CS80.

I was interested in CV myself,  especially given the control capabilities of 
these synths, however my understanding is that is actually harder to modify 
for CV than for midi.  

Does anyone in fact have such a CV mod on CS80 or others?  I would be 
surprised.