I should note that this attenuator is just a bit more difficult to install than the default pot. It is much smaller and the contact holes are smaller too, making multiple wire connections tricky. When screwed down, one channel sits very close to the plate, meaning you must be careful about soldering and wiring management to avoid shorting to the plate.
That said, it is easy enough to loosen or not even screw down the attenuator during construction (or upgrade) to make working with it easier. If I were doing it again, I'd also thread that first black wire from the braided set on page 21 of the manual through the two holes from the bottom, leaving a small 1/8" "post" on top to which to attach the 4 1/2" wire on page 22 that goes to the TRS terminals. This avoids having to try to get two wires through a hole that is too small.