The krazy glue may work fine. After I did as much research as I could on the subject I ended up using the 3M Plastic and Emblem adhesive. It worked out great and the spoilers have been back on the car for almost a year now.
I used painters tape to hold the glued welting down the length of the spoiler and let that dry for a few hours, and then formed the bends on each end, trimmed, glued and taped the same way, and let that dry overnight.
Turned out great IMO and they've been back on the car for close to a year.
This welting is nice and pliable and GREAT to work with! Perfect Polar White color match too!
John