Hello guys an gals.. Having a issuer with finding the factory wiring for the rest doors an tweeters in my brother 08 suburban 2500.. Doesn't have bose so no factory amp. My issue is I'm trying to use factory locations for mids an high but where I thought I found where they split won't let me use them in a cross over... Any help would be great of someone else has figured out how to use crossovers but use the factory wiring to split them up. Here's a picture of my butchery...

I know the speakers are the blues for one side an yellows for one side but I can't split them up to have the crossover send a signal to separate them