is the following a good upgrade?

So I plan on doing a "Car audio overhaul" to my car. I will tell you what I currently have, then I'll tell you what I plan to replace and I would like to know from you guys if you think it is worth it, or if I should keep a certain component or get a new component that I'm not already getting, etc..
also just so you know I'm going for sq not spl. But it is nice to have spl also :) So that is why I'm going for 2 subs.

Current:
-Pioneer DEH-7800mp
-JL Audio 4 gauge power/ground + 100AMP fuse
-generic distribution block 4 to 8 gauge
-Stinger 8 gauge power/ground
-Stinger and monster interconnects
-(2) infinity Kappa Perfect 12.1D subwoofers
-Alpine Type S Coaxials (rear)
-Alpine Type R components (front)
-MTX amp (dont know model) it is 70W rms x2 this is for components
-24 sq. ft. dynamat (I will not get any more sound deadening)
-Kenwood KAC-7252. recently blew out. This started the whole "overhaul"

What I want to replace
-replace infinity subs w/ (2) JL 12w6v2 4 ohm subs
-replace jl power/ground w/ kicker 1/0 gauge wiring kit.   https://www.sonicelectrnix.com/item_3935_Kicker+PKD1.html
-replace alpine type R components w/ diamond Audio HEX components
-new amp for subs. t10001bd(1000W @ 1 ohm, so I will wire subs parallel/parallel)'
-I will make 2 new boxes. Each box will be 1.5 cu ft. 3/4" MDF as specified by JL site

So is this a good upgrade? What kind of sound quality should I expect from this?
Also should I keep the alpine type R's and move them to the back or should I keep the coax back there? The rears are not powered since I'm going for good imaging.

thanks

i would move the components to the back and also amp them also and just turn down the gain on them compared to the fronts.  will keep the distortion to a minimum and  keep sq up.  and pick up a moderatly rated 4 channel amp, 75 x 4 or greater ir you choose.  those type r components can handle a lot i have the 5 1/4s in kicks in my car running of a 500.2 from rf.  and they scream .  so think twice before you can them. 

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you can do it....
advanced MECP, lol does it really matter....
patience is a virtue

thanks.
I love the Type R components but I know that the diamond Audio Hex components are better, I just didn't know if I should keep the alpines or not. I might do what you suggested and then hook the remote wire for the rear speakers to a switch that way I can turn off the back speakers when I'm playing sq music such as Iasca's sq cd.

Diamond Audio Hex S600s is what I've been running in the front of my car as my only set of full range speakers for about 4 years and I absolutely love them.

I would personally sell the set of speakers I wasn't planning on using and put that money toward the Hex components and put whatever you decide to keep in the back, that is if you even want speakers in the rear. Your choice.

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