BAT VK-60 stereo to mono jumper

Where is the jumper located to switch from mono to stereo? I changed it a bunch of years ago but forgot where it was.
near the front face of the amp, you will see a jumper that connects the 2 board together and it's not very long.

in addition to the jumper, you will also need to cut some output wires to return to stereo.
Since I now have this same problem, can someone provide more detail. The amp I have just purchased was originally stereo and got converted mono. I would like to convert is back to stereo.

Thanks for any info...
Just as Semi says: Remove the jumper, then either cut or unsolder the wires joining the 2 sets of speaker terminals. Those wires will be obvious. They only connect each set of terminals. Do not remove or cut the wires from the circuitboard(s) to the terminals.
Thanks to everyone. I sent a question of to BAT and got a four page set of instructions. Note that there are TWO sets of jumpers connecting the two boards inside. The jumpers at the front are the ones to be removed. Unknown what the function of the middle jumpers are.