I bought an ip68 strip from Montreal Led. They said to silicone the 3m tape on to the back, let it dry and cure then stick it to the side of your rv. Clean the area with rubbing alcohol first. The strip came 5 meters long but you can cut it if need be.
I also purchased Montreal led and the adhesive back did not stick in warm weather either,fine when cooler. I used,as the manufacturer suggested, GE SILICONE, very thin application, placed the strip and secured it with painters tape for a couple hours and it hasn't moved yet.