Ok, I'm still asking questions, I apologize but concerns keep popping up. So, the IR sensor Robo just sent me is slightly different from the original. The board is the same but the transmitter(s) and receiver on the new board are much, much smaller than the original. I did a quick measurement and found that the difference (on the y-axis) between the two is around 4-4.5 mm. My question is this, do I need to modify the Y_PROBE_OFFSET line in the Arduino code to compensate for this? Right now, the y-probe offset is +30. I've asked Robo, but I honestly have no idea when they will reply.