The white spirit/mineral spirits* method does seem to be the way.
However, two caveats from friends of mine that have tried this:
- this doesn't seem to work so well on small decals like stencils/maintenance markings
- it is NOT essential to do this, the decals will work fine as regular, everyday, plain-Jane decals with setting solution, etc.
Warren
* I found out the hard way that enamel paint thinner and mineral spirits were the same thing, THEY ARE NOT!!! Don't make that mistake.