Disconnect Cyrus 2 from mains.
Remove the amp top cover and locate the two fuses near the back? of the circuit board.
Remove said fuses, store safely and replace the cover.
The socket for the PSX used to have a form of blanking plate inserted into it. carefully prise it out, maybe getting it to tilt so a small screwdriver or strong tweezers can be used to remove it.
Position PSX to the right of the Cyrus 2, connect the umbilical and connect mains cable to the PSX only (if no vinyl used) or a second mains cable to the Cyrus 2 as well (the existing supply feeds the phono stage).
Switch PSX on and enjoy more power and weight in the sound
Tear down these walls; Cut the ties that held me
Crying out at the top of my voice; Tell me now if you can hear me