So I finally got this installed and it's a decent result, nothing too flash but certainly better than stock amp/speakers.
To install on E88 it is indeed much more involved - have to remove rear seats entirely, which takes a while and quite fiddly if you haven't don't it before - I posted a thread on the diy section on where I routed the wiring -
https://www.1addicts.com/forums/show....php?t=1522716
Hopefully if use to someone with E88 considering this