Well, I loosened up all of my exhaust joints, disconnected them, reconnected them, and re-tightened them. Good news is that I've reduced the leaks at the ball joints to so tiny they're not worth trying to make better. Bad news is that I must have shifted or damaged the head pipe gaskets during all the pipe manipulation, so now I have leaks there. Looks like I have to order new gaskets and do it all over again.