Honestly, don't worry about that. If you're running new components, you always want to run new wires to the tweeters. I recommend using the woofer wires as the crossover inputs, and running new wires from there to your new speakers.
If you just need to know, I would just test them as I am not sure (if you are doing something different). Just find an extra speaker and hook it up to see if it plays correctly in phase.
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