Two Skywriters on the same I2C bus

People,

I’m trying to connect two Skywriters on the same I2C bus. Looking at the MGC3130 datasheet, it is possible to chose either 0x42 or 0x43 for the slave addresses by pulling the IS1 and IS2 pins to either 00 or 10 respectively.

What this means is removing one resistor attached between pin 21 of the QFN and ground, and connecting a 10K resistor to VCC.

Question is: which resistor on the board is attached to which pin? the PCB tracks are not easy to trace at all.

What would even be more awesome is a schematic and PCB layout.

Any help gratefully received.