Couple modifications are required for proper output levels.

1) on PCB1 cut the trace

2) wire the pin on a header that was connected to a cut trace to a right pin of R38.

3) wire left pin to a ground thru 2K2 resistor

4) on PCB2 cut the race between pins 1&2 of IC8

5) solder 0603 11K resistor between these pins

6) solder 10K resistor from pin2 to a ground.