months ago I've bought this abused Tamiya Acto Power Off Roader 2wd Motor.

Now I'm in the condition to full restore it because I've bought a new endbell (with new brushes), a brand new armature and a MCI sticker to refresh also its cosmetic.
I've already made a deep cleaning of the can (and probably I will repaint it) and of the other parts not destinated to be replaced with new ones and the only doubt I got is about magnets: I'm not in the condition to zap it but I need to know if there is a empiric and manual test to do to understand if they're gone or if they're still fine.