Callaham Upgrade Kit, Bigsby B5/B7 Front Roller

We've done this particular upgrade on a bunch of B5s and B7s, as we sell these complete bridges with all upgrades installed. Sometimes these small shafts are a bear to get in, but we're always able to - we have a little H-frame press that we use when one is stubborn. The fact that they ultimately always go in indicates that the shaft properly fits the hole, but it's only slightly looser than a slip fit, so any small obstruction will prevent it from being easily pushed in with finger pressure. Two possible causes: 1) the two holes on the outer frame are not perfectly in line with each other; 2) there's a burr where Bigsby has drilled and tapped a hole for the setscrew that holds the shaft in.

95% of the time or maybe more, we can push the shaft in with just finger pressure, but now and then there's one that is just too tight, in which case we go to the press, and that always does the trick. Tapping lightly with a plastic or brass hammer should do the trick for those who don't own a press, but we wouldn't suggest hitting the shaft with a steel hammer, as you might bend or deform it. In any case, sorry you had trouble with yours!