Not to concern your self I will be paddling a Magic or Rob Roy with a QJ sticker on it.  I am selling my tandem and a prospective customer ask what it was and could it be removed.  When I posted that I figured some one would suggest a hole saw.

I've removed a few decals from my composite canoes by carefully lifting a corner with a razor blade and slowly peeling away.  It helps to let it sit in the sun for a bit to heat it up before starting.  If the decal tears, I just use the razor blade to lift the edge and start again.  In my experience, most of the adhesive has stayed with the decal.  Whats left I removed using a citrus product - I think it is called Goo Gone.

FWIW - If the mfg was no help, I'd try heat and a blade. For any adhesive residue, goof-off type stuff would be my last choice after sandpaper and a router failed. Rubber Cement Pickups or your thumb, w/ nail if needed and elbow grease would be first. Then cooking oil.

As far as the aggressive solvents go I don't know what might react with epoxy or gelcoats but I'd start with simple solvents like alcohol, naphtha, spirits ... before I got to the end of the alphabet type solvents contained in most one product eats all blends. All would be used sparingly.

I don't know what contact cement solvent contains but I know whatever is in it is  gelcoat safe for a brief amount of time and I've used denatured to clean epoxy before resurfacing with no ill effects.

Start small. Do no harm. Let us know.

Hey MagicPaddler,
Quote her a price for the decal and tell her you'll throw the canoe in for free.

//Windsailor