I am putting a set of components in a friend's daughter's car, and I would like to avoid running new wires...

'95 Maxima, factory front door speakers are components (I think this means it was a Bose system).
Already has an aftermarket stereo.

From what I can tell from the wiring diagrams, the head unit connects to the Left Front on Yellow - and Brown +. Right Front on Light Green - and Purple +.

This is where I connect the aftermarket crossover... right?

I just want to make sure I'm correct.

 

If the car came with a Bose system originally, there will be tweeters in the windshield pillars. Non-Bose radios did not come with tweeters

In the Nissan wire harness for a Bose radio,
driver's front speaker: + is yellow, - is brown
passenger front speaker: + is purple, - is light green

For the non-Bose radio (just in case),
driver's front speaker: + is blue/white stripe, - is blue/yellow stripe
passenger front speaker: + is brown, - is brown/white stripe

 

Correction, it is a 97 Maxima. The factory tweeters are in the door, upper front corner.

Where is the factory crossover located? The wire diagram implies that the crossover is on the factory woofer.