I have never heard of a Vauxhall 2.0 V6. I am sure they just make 2.0 16v 4cylinders, 2.2 16v 4 cylinders, 2.5 V6 24v 6 cylinders and 2.6 V6 24v 6 cylinders.
Thanks for the answers guys. The reason I was asking is that I've just bought an sri 2.0 16v but when i got the new v5 document back, it was registered as an sri V6 24v 1998cc and my insurance reckoned there was no such car. So it looks like a mistake by the DVLA. Will phone them tommorow.
Thanks again for your help :-)