Ok so is the right red or white?
Honestly, I forget. I don't have any of the digikey jacks on hand to look at. Besides, it doesn't matter that much, as long as the input coloring is the same as the output coloring. Then channels will match. The only way to tell is when you're done and try out the balance control. You'll know if the cables are plugged in right or not. If they are wrong, just move them.
Minus the balance control, everything is basically a dual-mono design. It doesn't matter which channel you decide to define as left or right.
jh