The best results would come from installing a purifier at the positive terminal of each driver. This is fairly easy to do: unscrew the front mounting screws that attach the driver to the speaker box and carefully lift them out and then unsolder the positive lead and place the bybee at the positive and resolder. Be careful to cover the speaker cone in the area near the terminal where you will be soldering with a sheet of paper or something similar to prevent possible splatter from hot solder as you solder from landing on the speaker cone.
BTW: Installing the bybees has been the most effective tweak that I have done---and I'm a habitual tweaker. I have installed them in all of my electronics, pwr supplies, digital out of dac, and audio out terminals, but the most effective placement has been at the positive terminal of each driver.