Checked out the B-tension bolt on my mountain bike - it was a little longer. Swapped it with my road bike bolt - screwed in the regular way (to the max), the spacing is about the same as the other screw upside down. It is kinda the law of diminishing returns here - a curved/bent bolt would probably be more effective.

Just how much space is the minimum between the sprocket and pulley? I'm wondering if it is adequate if I'm not hearing anything. But it sure is close!