couple of options.....
soak it in industrial grade ammonia
other option is Freeze-off this is like PM blaster on steroids....it has pb blaster type penetrating oil and combines with super cold temps (cooling as liquid goes to gas for physics type) try multiple cycles with some tapping, the super cold can often break loose things beyond what just penetrating oil can do
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Life is too short not to ride the best bike you have, as much as you can
(looking for Torpado Super light frame/fork or for Raleigh International frame fork 58cm)