All we need to do is reverse inputs and outputs, cut connections to ground on outputs,
remove 75R resistors on outputs.
Refer to schematic. Output relays are connected to ground when output is muted.
Remove R 3,4,5,6,7,8.
Cut bottom layer traces as shown on pictures (white lines).
Reverse input and output with shielded cable, no need to use Monster diameter 12mm,
use something like Mogami line level cable.
Write IN 1,2 instead of MON1,2 on controller.
Write OUT1,2,3,4, instead of IN1,2,3,4 on controller.
SUB can be used as monitor output now (out to meter/phones without level,
paralleled to CRM source of input selector).
Previous METER output comes after level now.
Termination switch (DIP-3), relays ZL and ZR are useless as well, remove it and install
proper terminations on speaker outputs itselves if needed.
Logic is next: attenuator's load should be 3k, and it is allready terminated with 4k3 (RL1....4).
Hope everything is clear.

