There is liquid paint remover sold as "aircraft" which will dissolve epoxies and 2 stage paints. However, bead blasting, done with the right media and pressure, is the best prep for the frame as it provides the mechanical adhesion plus exposes fresh metal for primer adhesion.
As far as the decals, no information on that sorry.
Gary Watts Vancouver, WA USA
Hi, I am restoring one of my first bikes, a 1957-59 Raleigh Record. I am in need of some decals for it. My dad painted over everything with Imron aircraft paint in the mid 1970s and I can't get it off without bead blasting
Tom Cagan, San Fernando Valley, California