Rust stain in vinyl headlining

[Dazedkipper]

Had a deck fitting that wasn't watertight and rusted a bit, the rusty water has soaked into the headlining vinyl. Suggestions to remove? I'm thinking good ole Oxalic Acid.....

 

[Rigger Mortice]

I'm thinking the same.

 

[nigelmercier]

Great minds ...