Hi Eddy,
unfortunately, I don't have the CVP-709 Service Manual (SM) at the moment. But maybe the CVP-609 SM will help you. This instrument is probably very similar in construction, but has a "NW" (Natural Wood) keyboard, as opposed to the CVP-709's "NWX" (Natural Wood X) keyboard.
If you are interested in the CVP-609 SM, please contact me via PM (personal message).
Best regards,
Chris