Re: JB sh-4 or JB tb-4
It's debatable. String balance (and evenness of tone from string to string) are better if each string lines up with it's poles. It depends on how far off it is and how much compression you play with.
Most newer guitars are tending towards wider spacing at the bridge, so if you aren't sure I'd go with the TB-4.
Others who collect older Gibsons will argue to get what fits best there (SH-4).
Easiest way to tell for sure is to measure the E to E string spacing. 50mm or below, it's SH. Otherwise, TB.