I used the 3MM tape but the one thats thick. I just stuck the tape all around the edge and also inside so that there are no gaps.
otherwise there will be water and debris going inside.
There is a link above with the template that a user posted. If not than i attached one here. I did install it on my 16 and it worked out perfect. Make sure you print it out on a 100% scale.
Thanks mrasdf,
As you said i printed it with 100% scale and magic, the holes fitted perfect including the truck measurement. Gonna install it this week and update with pictures.
Thanks again to all who helped.:)
Its a 2018 performance pk spoiler getting installed on my 2016 GT. From what i have read if you have the stock spoiler it fits right through. Mine came in spoiler less, so the drilling. The template will work, a little off, but i figured it out. Will update with the install.
I printed the template exactly the way and size that was there on the pdf. Keeping the middle hole in place the other ones were out of place. (but close) But i'll probably try to make it work. I am attaching pictures below.