I am at this step and wanting to confirm if I have bad cables before I start modifying them.
Here is what I have.
And here is what is in the build guide.
https://d17kynu4zpq5hy.cloudfront.net/igi/makertech-3d/MskBDrdaMRmKAMRd.medium
Note that the red side is correct on the LCD panel, but backwards on the control board. Just wanting to confirm this means I have bad cables and need to modify one end to fit backwards.
Double check that EXP1 on the board goes to EXP1 on the LCD board and the same with EXP2. I had them swapped and was having major WTF's for a while. In the end I had to cut the tab on EXP1 and flip it backwards. I did this on the LCD screen side, but I don't think that makes a difference.
These are not correct. You will have to modify one end to fit backwards. I had mine like you have yours now and the lcd did not light up, I modified both cables and it works now.