Retrofit Subwoofer on High Performance w/o Subwoofer

[thermal-fixity]

The next upgrade is to add two Harman Kardon center dash speakers instead of the one I have with my High Performance system. Any chance someone has done that and could share your experience?

• Where is the HK tweeter (smaller) speaker is to be connected to?
  
• The mid (larger) speaker is to be connected to the AUD 10/2 pins. My XC90 already has a plug for it and the wires running to the white plug behind the passenger's footwell. So, I'm going to just take it from there and run to the AUD.
  

My current HP tweeter is not connected to the AUD. ChatGpt says that the current tweeter runs to the IHU and only used the system sounds and not music. Chat says the tweeter is eventually to be connected to the same AUD 10/2 pins but I cannot find any confirmation online.

Should the tweeter wires just be simply joined with the mid channel?