Pliability/maneuverability problems with Heller decals

I'm building an excellent Heller Subaru WRC rally car.  I bought the kit on clearance so it's about 5 years old.  The decals are not brittle, but they have no pliability or "slide-ability".  Once they hit the paint, they can't be moved without tearing.  This hasn't been a problem with the smaller decals, but now I'm ready for the large decorative decals and how they look will make or break the model.  I use Solvaset for snuggling decals down over uneven surfaces, but I've never run into this problem before and don't know what techniques and products are available.  Heller's directions just say to use "warm water" and give them a 10 second soak, which is exactly what I did at first.  Then I gave them a longer soak and still no difference.