G'Day Ben, thanks for that, yeah I saw that auction and fell about laughing, I've got half a dozen of those potmetal adapters hanging in my garage, I must buy some more coolers and sell them as a "set", in fact I can do one now as I've bought a CB900 cooler for my racer project and I'll adapt it to suit my "Terry-Built" adapter, so I can sell a nice Derale cooler "set" I've been saving, on EvilBay.
So what was wrong with your rooted head? Was it fin damage, or valve problems? Clyde reckons that F1 heads are probably the best you can put on either a K or even an F2, and I'm inclined to agree with him. Cheers, Terry.