I've had the same exact problem in the three years I've had my car. I mentioned it here a while back, and someone suggested it might be the throwout bearing. It doesn't get better or worse, and it doesn't seem to affect the clutch's operation, so I just live with it. To paraphrase Rocky IV: If it dies, it dies.
I also read something in one of those "ask the mechanic columns" in a newspaper or magazine or something where someone said the MTX-75 can make some funny noises or something, and Ford said it was just fine.
