E90Perf spoiler 3m install ?

I have read many DIY however have not 100% determined where the 3M needs to be applied. I see many people say 1/8th from edge of lip but what about in the middle on the second lip, any tape there? Would appreciate any input.

2nd lip? This is for the trunk spoiler? what do you mean by 2nd lip?

here's the DIY: http://www.m3post.com/forums/showthread.php?t=437947

Flying Ace wrote

2nd lip? This is for the trunk spoiler? what do you mean by 2nd lip?

here's the DIY: http://www.m3post.com/forums/showthread.php?t=437947

Underneath, along the middle the rolled lip finished in CF that rests on the trunk.