Things to do include cover the rest of the inner door skin with dodo dead mat black, make up some speaker brackets to fit the 6.5" midrange speakers in the stock location
I'm also going to rip out the rest of the interior and cover the floor with more silent coat to help stop any other vibrations and fit a JBL 3 channel amp which will power the fronts with 75w and 400w for the subwoofer which i haven't quite decided on yet but think i'll be getting a JL audio 10W3 which works in a small space as i can just fit a subwoofer box behind the drivers (or passengers) seat