First of all, Welcome To
Build looks awesome. I didn't have the guts to....well.......gut my rear panels like that, but you went for it in the biggest way. Looking at your amps, you're going to have incredible head room.
You might be surprised at what you find around here.....
Man...... I want those amps.
I'm still toying with the idea of replacing my amps with two Mosconi AS200.4's and a Mosconi Zero 1. Then I'll probably replace my fronts with Focal Utopia Be No7 Active or 165 KRX3 Power. The Utopias sounded a little harsh to my ears, so I'm thinking I want the KRX3's. I may just leave my T1692's in the rear as my wife believes that my son needs to hear music, and not booming bass. I actually like my subs, so I'll probably keep them. I love my 3Sixty.3 - it has been perfect for when I like to be juvenile and crank the bass up. Usually I turn it up and have a laugh, and then return it to normalcy.
On the other hand, I may just keep my Rockford stuff. A lot of people talk terrible of Rockford these days, but the more listening time I get in my car (not a daily driver), the more I really like the way it sounds. I would definitely be easier and cheaper to just leave it as it is.
I really should do one of these build threads some day.
Good luck with the stock head. I spent a couple hundred bucks and probably 30+ hours of troubleshooting just trying to keep it in my build. With those Mosconis being class A/B, I'll be waiting to hear if you get the speaker pop/click/thump.