I have had good luck with fresh applications by first sealing the decal to the sheet with a good fuel proof paint. Then after it is completly dry, 24hrs, cut it to the shape you want and slide it to the CLEAN surface. Then seal it again with more clear fuel proof paint. Let the hole job cure for 24 hours. Take your time and things should be good.

I have even been able to apply decals to old surfaces by cleaning the covering with acetone, then alcohol. And then follow the above directions. I have been using my own inkjet printed waterslide decals with reasonable sucess.

Good luck,
Al