I've tried Peelaway 7, the safer one and it worked fine, didn't get any of the paper to stick to the paste, it simply peeled off and I had to get the rest of the gunk off with the spatula which is pretty annoying on complicated surfaces. Today I've tried the Peelaway 1, works faster and well, but it's also annoying due to all the paste left over, especially in the tight spots. If you can't get access to peel stuff off in one go it becomes really messy with the paste smearing all over with the half melted paint inside, thus colouring other already clean areas.

I guess something aggressive would've worked better on these cast parts, dipping and leaving for a while is probably the only way to work this quick.