Start with one of these. they swivel the wrong way so you have turn the handle 90 degrees
1] Remove the pad, you won't need that
2] On the underside of the handle there is a small phillips self tapping screw,
Undo it and you can remove the handle .
3] when you take the handle off you will see two small plastic bits on the end, snip these off, you will also notice that two of the sides are slightly flattened, take a rough file or surform and make two flats on the rounded edges so that you now have 4 flattened edges.
When you have done this the handle will locate in the 90 degree position, and can be fitted.
4] You now have a hole where the phillips screw was, but you have to drill a small hole through this one so that your self tapper can get a new start.
You pad plate is now swiveling the way you want it to, just cut this plate to fit your brush, The superlite is perfect because you only have to take the piece off that the pole screws into,
you then fasten the new plate and swivel with 2 self tappers.
I drill the holes for these at an angle, so that the screw don't go right through the brush stock and scratch the glass.
You can also use a brush like the Bentley, but if you do you will have to cut off the bit that the pole screws into, leaving the top flat.