Hello all, I am doing some updates on a K2 that has the Yaesu tuning knob that is very popular. I can't seem to find a wrench to loosen the set screw on the knob. I am hoping that it is a metric size and I just need to find the right size wrench. Otherwise, I fear the set screw may be stripped out. Can anyone tell me the correct wrench size for these things? Thanks very much. Doug W4DAS