I have a stratocaster that at the moment has a noticeable amount of rust on the pickups.

can i clean these with steel wool or something, or is the rust enough to trash them for good?
Rust doesn't affect pickups in any way other than cosmetically. I used this stuff called Must for Rust on my Ibanez, but you may want to look for something else. MfR is really strong, and it actually took the silver color poles off of the pickups a bit in places. Again, this doesn't affect sound at all, it's really really hard to damage pickups in any way, it's just cosmetics.
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o_o My dad's name is J Wyatt. XD Crazy. Anyways, yeah, a rusty pickup won't really do any harm, but I'm sure there's some solvants out there for it.
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Nah, I prefer to tune lower. My tunings usually go into weird Hebrew symbols.
I tried steel wool on an old Hagstrom with rusty pups. They seemed to re-oxidize again very quickly. In retrospect, I realize that scouring the rust also scoured the chrome leaving the metal bare to the elements.
Water which is too pure has no fish - Ts'ai Ken T'an