I have 2 pinhole leaks in my radiator-upper driver side front. I have seen stop leak products at auto stores. Is this a permanent or temporary fix? How does it hold up-good or not so good? How about soldering it? What solder would be best? I remember back in high school-1980 graduate-my friend put a couple of Bayer aspirin in his radiator-I thought he was nuts-but he said it works,but that is not an option for me. I eventually plan on getting a new radiator,but i dont see having the $ for that until at least spring. Looking forward to some replies.Thanks Jim.