Personally, although it might not be broke, I'd always remove a BAII. One of the more useless things you can do to a Fender bass, IMHO...
Not only that, but even the slight extra robustness of, for example, the Wilkinson, or later Hi-Mass bridges, is irrelevant. No BBOT was ever too flimsy to do its job properly. On the three-hole USA basses of later years, I would say that the BAIII was a worthwhile upgrade, if only for the extra intonation travel. However, if it ain't, etc etc...