Audi A7 audio upgrade

Hi guys I’m new on here and this is my first thread. 

Ive purchased a Bitdi and not really happy with the audio so wanted to know if anyone has done a how to tutorial on and install please. 

With it being a non bose set up I’m going to get the bose door cards to put in the 3 way components I took out from my q7 

the door card removal looks straight forward 

but has anyone done the tweeter removal from the dash and of so how please I have also got the heads up display on the dash too. 

So basically I want to know the wiring method of what to tap into from the boot side please 

I’m going to run 

4 channel amp for speakers

sub amp

audison signal processor 

from the standard head unit 

thanks very much in advance