It would fit but your vis valves would be redundant, therefore not as powerful as the original set up. You will be down on torque and bhp, how much I would not know but guess similar to the car it came out of. Not sure if anyone has done this on here.
According to Parkers guide the KV6 produced 172 to 175 HP depending on version etc. But would that manifold even fit under a ZS bonnet ? and if it did what would the power and torque delivery be like ?