You may be surprised at the wonders of oxalic acid. It's sold as wood bleach in crystal powder form, which you dilute in water (~1 tablespoon per gallon). You can usually find a cheap kiddie pool at Wallmart for under $10 for soaking. Toss in the steel parts, too, but not the aluminum parts. There are lots of threads on Oxalic Acid (search: "oxalic acid site:bikeforums.net")

I picked up a '68 Schwinn Speedster in similar condition and it cleaned up nicely. Those bars may not be a total loss.

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