Strong magnets are a BIG no-no especially on the vintage spec pickups. The magnets in the pickups are very sensitive to strong magnets and will ruin your pickups...
Are magnets bad for guitars?
No, they already are magnets, it's not like hard drives or computer screens. if you put a magnet near/on them it will most likely distort the sound in some weird way but wouldn't ruin them.
What damages guitar pickups?
Improper winding: If a pickup is wound improperly, kinks may appear in the wire. These will eventually cause the wire to break. Foreign objects: Foreign objects (notably steel wool or shards of metal) can come into contact with the pickup coils, causing significant damage.
Why do guitar pickups have magnets?
A guitar pickup's magnet or magnets provide(s) the power that enables it to do its thing by sensing the movement of the guitar's steel strings when you play. Different types of guitar pickups use different numbers of magnets, usually one, two, or six, depending on their design.