I need help getting my reverse lights to come on
 

I have a used manual swapped em2 d17a2 that uses a range switch in order to start. Drives just fine while selected in P mode, only thing is my reverse lights don't come on. I know already that it's a white wire or something that you cut and connect to green/white stripe wire coming into the top of the grey plug near the ecu. I also hear there's a need for a second wire that is solid yellow to be cut. I may have already messed up because I have a yellow/black stripe wire and a yellow/red stripe wire . I cut the yellow/black and it was the ecu connecter.... So I'm not sure where to go with this. Anything helps !