Ok, don't use acetone guys. Use a small safety pin and carefully push against the top foil layer under an angle of approximately 45 degrees in one of the corners. The pin is above the card, but you're kinda pushing up, trying to get under the foil layer from above as it were. When the foil layer comes off, use a pincer to pull it off a bit more, then use pull it off very slowly with your hands, making sure the foil layer is folded back on itself. That worked a whole lot better then using acetone, which just makes the paper layer under the foil layer tear off way too easily.
I think I have around 30 blank cards now, ready for custom lands! As soon as the decal sheets arrive that is