Hey, that looks really interesting! Could you explain how the bender is actuated as part of the Bigsby? Or point to another thread if you've posted on this before? Appreciated!
The "B-Blender" is basically a modified arm for a Bigsby which converts it to a b-bender of a sort. In the playing position when you gently pull up (vertically) on the arm, only the b string is actuated. Otherwise it behaves independently like a normal Bigs (on all strings) with horizontal movement of the arm. The thumbscrew (down by the tone pot) fine-tunes the pitch of the up-bent note.
It does require some adjustment of right-hand picking technique. Typically I hook my pinky around the notch at the end of the arm to bend & release while playing.
You can imagine there are a variety of opinions on it, being hand-actuated plus a Bigsby & all.... I'm not a real bender player, but it allows me to pretend & I enjoy it. Hope this helps!