Thanks. I did same for mine. Betalink is some nasty stuff. Make sure to cut the entire end off one side. I poked holes with a pen and at the end it kept wanting to push out of the funnel!!!
As for my install, I removed the rear spoiler with dental floss and trim removal tools. If you work from each end and meet in the center it came right up. To clean off the excess double sided sticky tape, I found that using your finger to roll it upon itself worked amazing. The hole thing was done in 15m! Then you just clean it with solvent and test fit the wing. I made it equal on both sides then taped it to the car in the middle.
I then taped both spoiler and surrounding painted areas with frog tape and used a nice thin bead of the betalink after sanding the spoiler and cleaning all areas with solvent. It came out great with only a few spots of excess. The spoiler is really on there! I was able to use a plastic trim removal tool to rub the excess off and then followed up with the solvent and quick detail. No prob.
One thing to note, maybe don't leave tape on the bottom painted areas on the udnerside of the spoiler in the middle as some of the tape became trapped under the betalink!! I had to score it lightly with a razor blade then use the trim tool to remove with and then solvent and quick detail. I'll post pics soon. Thanks!
FYI, I also left my front spoilers just taped with 3m in case of cracking and easy removal.
I have to say the spoiler is MASSIVE! I can see it from my rear view mirror! It looks so sick. Glad I did it. It was actually TONS easier than the front spoilers.