So I finally decided to replace my factory deck. I have an H3T Alpha with the factory 6-disc changer.
I replaced the door speakers last fall, ran into a surprise with the 4-wire rear 6x9's but they seem to be acting like subs and sound alright with what I put in.
Front Speakers - Polk Audio DB651 6.5-Inch Coaxial Speakers
Rear Speakers - JBL GTO938 6-Inch x 9-Inch

My plan is to replace the deck, I want to retain SiriusXM so already purchased the XSV300
I also got the 40-GM10 radio antenna adapter & Metra 95-3304 dash kit
For the deck I think I'm going to buy the Sony XAV-AX7000 as it has a higher wattage output and I don't want to screw with an amp

What's left is the following I hope to get some assistance with:
- Tweeters, should I replace them while I'm already doing this work?
- I have an OEM backup camera in the rear view mirror, is there an easy way to move this or duplicate the image to my new deck?
- I want to retain Onstar, chimes, Rapp etc, from what I've read the GMOS-100 was the correct module but is discontinued, would the GMOS-04 work for me?
- Also I saw video where you can remove the antenna connector from the factory XM remove the plug case and connect directly into the XSV300, so I think I'm good there
- I know I'll probably have to run separate power for the higher output deck as well

Have I missed anything else or made any mistakes here?

Thanks in advance!