Thanks Dan, there was a lot of info out there but definitely plenty of things I picked up along the way. Better for others to pick up some tips here than to spend the money and not have the right parts.
Riksta - speakers in the front + rear doors are 6.5 inch, with plastic spacers held in with rivets that you drill out. You can replace these spacers with MDF ones you make yourself or plastic ones that screw straight in,
like this. Not entirely sure on the tweeters, although pretty sure most are 2 inch and come with fitting kits so they fit most cars.
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2006 LX FOCUS SEDAN
Titanium Grey, factory bodykit, slightly debadged
CSA Motorvatr 17's/Kumho KU31's, Eibach Prokit/Lovells rear springs, Koni Sports Kit
Lower airbox removed, K&N Panel filter
Momo gear knob + boot + pedals, Ghia boot garnish, Zetec Chrome interior door handles
JVC KW-XR816 Headunit + more to come...