I'm not sure, but a good, thorough cleaning is probably impossible without some sort of disassembly.

But if all you want to do is clean the heads (assuming everything else in the drive is in good working order), then all you need is a head cleaning kit. I've never used one, but this is my understanding of what they are and how they worked: They usually had a felt disk, on to which you applied some sort of fluid. Then when you inserted the disk into the drive, the heads would run across the disk, cleaning them. Then it would eject.

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