A mk2 Golf GTI 16v rad fits IIRC, I fitted one to my mk2 Golf when I G'd that years ago. I noticed the 1.3 Golf one was the same mounts as a G40 one, and I had a 16v rad already, offered that up and again, same mounts so I went with that, so if the mounts are the same then it should fit, it's also got more cores in it I think so will cool even better. However, it may be overkill and actually cool too much? I've never had a problem with overheating on a Polo, it's normally the opposite!