So I want to install a spoiler on my SV, its fully loaded with everything except the spoiler and I feel like spoilers on these tie the back end in so well.

Has anyone installed one manually? OR would you guys suggest I let dealer/bodyshop do it? I am good with my hands and all but don't think I like drilling holes in my trunk if that is necessary.

Am I better off buying one off ebay or amazon and then taking it to dealer to install or should I let the dealer do the whole thing? The ones you buy online are they just like the factory ones?

 

I got mine through the dealer and had them install it for warranty reasons. Plus the one they order is a guaranteed paint match versus who know what you'll get on ebay. Will it really match? Who knows.
There is an led brake light in it so obviously wiring needs to be done hence letting them do it for warranty reasons.
Costs a little extra but I thought it made sense. Looks perfect makes a huge difference on the car as you said it ties it all together.

 

I installed one on my 5th gen maxima, got it from spoilers.com (or something like that) and it was a perfect OEM match even came with the correct paint. Installing it was easy after you get past the part of drilling the holes in the trunk lid. Just make sure you line everything up just right and drill away. Remember measure three times then check it again before you drill. If it's not on straight or centered it will surely tell. Paint the holes to prevent future rust. I spliced the brake wire into the third brake light then removed the bulb from the third brake light houseing. I didn't bother removing the housing has you could not see it through the window tint. The whole job took me about three hours.

 

High Gear Auto Parts on Ebay has the Maxima spoiler and it matches the factory one perfectly. Also perfect color match on my buddies Max.

Just search "Maxima factory style spoiler" on Ebay. I think it's $149 shipped and painted

EDIT. It's $146.99