Hi, I just picked up some JB Weld and applied it this morning. Good news: the radiator isn't spurting water out anymore. Bad news: there seems to be a very small hole(which I can't see) that the JB Weld didn't get to, as there is a small drip from the rad every 5-10 minutes or so. I've been researching different ways to take care of very small holes in rads and came down to two things: PERM-O-SEAL or ground pepper. Of course, the last one would probably be a lot less preferable. Do you think going with the PERM-O-SEAL would be a good idea? I've heard people saying it works well for small leaks in car rads but am unsure of how it would affect a WC system.
You really should try contacting swiftech again. Your damage was caused by using their product, following their directions. They should replace your radiator at no charge to you. Just my .02