Coming from an SV21 owner and having done all this the hard way(myself), take the map pockets off and mount the mid drivers between the lower left corner of the door and the window winder. So mark on the trim where the winder goes in a circle so u dont have any issues later.
User an MDF spacer screwed seperately to the trim. You'll have to cut a hole in the metal behind the trim, but don't worry it won't screw up ur door opening and closing.
Mount the Tweaters on the A-pillars as close to the dash as possible but so they are pointed directly at the opposite seat/side of the car.(the driver's side will obviosly be higher.