aircraft painting

[dixonreg]

I wonder if anyone who is involved with aircraft repainting can help me with a problem, or point me to a source of appropriate information?
I have an aircraft covered with synthetic fabric, in good condition. The paint finish is two-part polyurethane. There is some lettering in sign-writers enamel which I wish to remove, and this seems to have been successfully done in the past, when some letters were removed, then renewed.
I was told by the vendor of the aircraft (no longer traceable), that there was a suitable solvent which would selectively remove the enamel only, but have been unable to learn what it might be -if indeed the information is correct.
Eternal gratitude awaits anyone who can help.

[Nopax,thanx]

If memory serves, cellulose thinners will go for enamel but won't touch 2-pack (poly) finishes. Maybe worth trying a little on a cloth to see what happens.

I am prepared to be shot down on this, however.....

[Rocket2]

Dixon - my painter says to use an alchohol based thinner, use it sparingly & wipe off the residue quickly. Best of luck.