I went to replace the thermostat and snapped the top of one of the bolts off. I might have thrown it away or just thrown it during my fit of anger. But Im trying to figure out which size bolts I need, because the other is rusted even more than the one that broke, and i'm positive that one will break too.. Not one "auto" store around me has any idea at all of how long or what diameter I need. Any suggestions or idea of where I can find out? The engine size is a V6 3.0L.