Here's what I did when I took mine for painting:
1) Lift hatch & remove each screw on both ends of the spoiler (10mm).
2) Remove 4 round plastic covers on hatch which will disclose screws under those covers.
3) Remove the screws CAREFULLY or you will drop it in the hatch frame & it will be tough to get it out without using a long magnetic flexible thingy. I still havn't retrived one of my screws that fell in there.
Use a 10mm ratchet with an extension because it's about 1.0" - 1.5" deep.
4) When all screws are removed, at the center there's a 'V' clip that holds the spoiler down. THIS IS TOUGH TO GET OUT because of limited space. The hole is not big enough to place you fingers and squeeze it. I even used a small angled pliers and it wouldn't fit. I ended up breaking one side of the 'V' clip to get it out. Remember, DO NOT BREAK the whole 'V' clip. It also acts as a spacer between the frame of the hatch and the spoiler.
If there's a better way of doing this, then by all means do it. I'm just telling you how I did it and frankly it's a pain. But the final product is a joy.
5) Once spoiler is removed, remove the 3rd brake light. Again, BE CAREFUL. I ended up snapping one of the tabs on the small lens cover (located at the right hand side of the brake light lens) to access the small screw that holds the 3rd brake light to the spoiler. Use a very small flat screwdriver (the one they use to tighten screws on eyeglasses). Have the courage to snap it out. Use TLC. It's the only way.
6) Once the lens cover is removed, remove the small screw and pop out the 3rd brake light housing.
7) Disconnect the washer hose by removing the screw that holds it to the spoiler. It's located at the bottom of the jet spray.
8) Remove brake light wiring.
9) CONGRATULATIONS! You can now have the spoiler painted. While you're at it, have your rocker panels painted too. Looks great.
10) When putting everything together, do everything in reverse but please BE CAREFUL. It's the same care you have to do when putting it back ... because of the screws falling, breaking another tab, etc.
Removing the rockers is a different story. I do not know how to take it out. I just had the guys who painted my spoiler to take it out and paint it. Didn't have the heart to snap it out 'coz it's too tight and there's no play on it.
GOOD LUCK!!!
Kuruma Hayai