Exactly how much work is involved in fitting 6" or 6.5" components in the front doors and where`s the best place to hide the crossovers?

Cheers

 

Half an hour with a jigsaw and some 12mm MDF, to make up some spacers, plus another half an hour to take the trim off, connect the wires, remove old speakers etc. Per door if you've not done it before, less if you know what you're doing. See our favourite moderator's website FAQ .

There are numerous places you can "lose" crossovers. I made up a little bracket to site mine just behind the speakers but off the door itself - to let water flow past and out the drain hole.