There is a product by Floquil/Polly S called Easy Lift Off. Great stuff. I've used it with great success on vintage styrene kits that were painted with that nasty thick enamel paint that gave you a headache if you used it in a closed room (you know, the good old days.....)
Apply it with a brush and let it sit overnight. Then, go in with a stiff brush (like a toothbrush) and scrub it away. Somethimes the paint just lifts off in one piece. Easy. Guess that's where they got the name.
GK
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