I'd get a better penetrating oil than WD40, i.e. Plus Gas, as a start. If you can leave it submerged in some overnight to really allow it to soak in. If that fails you're getting into hacksaw territory...
@andyp started
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I'd get a better penetrating oil than WD40, i.e. Plus Gas, as a start. If you can leave it submerged in some overnight to really allow it to soak in.
If that fails you're getting into hacksaw territory...