All you had to do was remove your B string (or any other you preferred) and slip it over the tailpiece and tighten down the Allen screws on each side which went into the hole where the string was. The Allen screws were hollow so the string could pass through them after being hooked at the rear of the bender.
Then you'd just put a string back on, tune 'er up, and you were ready for some bending. I have two of these devices at the moment but only have one installed on an old Memphis Les Paul copy that I'm using like a slide guitar or lapsteel. It bends the 2nd sting B to C# out of an open E tuning.
My other one I had on a Les Paul in standard guitar tuning for the B string but I got a McEwan bender installed on it a couple of years ago so it's in a drawer. The bender operates like a "palm pedal" in that you push it down to raise the pitch of the string(s)...
You can find these from time to time on Ebay or Craig's List. I bought the last one I have for only $12 plus shipping........Here's some shot(s) of it....JH in Va.


