Hey! I've also been on the market to get new speakers and I was in the same situation as you. After digging for a while, this is the only part that I can find that may help out our situation.
Hopefully it works out for you(unless you directly wired it or found something else lmao) I'm possibly going to order them as well, but I still want to see what speakers I want to get, so I'm going wait on it for a bit.
I've got an update regarding my speaker situation. It's not worth to look for those harness, you can re-use them when wiring and soldering your new speakers, but honestly, just directly wire it, much easier to do if you know what you're doing.
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