You will have to take the door panels off to get to them. Also, you don't need a custom enclosure for the door. Just build some custom Baffles. Get some 1/4" Birch or MDF if it's available. Use the 4x6 mounting plates to build a baffle around the screw holes. But make sure you leave areas for the plastic snaps to go back in the door. Took me a couple tries to get it just right, but it's well worth it in my opinion. 4x6's suck balls. 6.5's are WAY better.
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