will the Corsair TX650 V2 fit in the zalman z9 plus and are the cables long enough to hide them behind the mobo panel?
Yes to the first question.
...As to being able to hide the cables? Probably all of the cables but the 4/8 pin cpu connector. These are hardly ever long enough to tuck behind the mobo tray esp. in the less powerful psu's. Typically the higher in wattage the longer cables they (manufacturers) give you. So unless you have an extension don't plan on it being long enough.