>>63842981
spray with wd40, ballistol, hammerite whatever oil
put in plastic bag
wait a day
go over it with soft a brass brush (spark plug brushes f.i.) or copper kettle cleaning pad and scratch rust blooms off
now you must decide:
keep it blank and oiled to prevent further rust
or
reblue the blank spots with quick blueing liquid, it will be a better rust protection but more work since you must degrease the blank spots

finish will look a bit specky in both ways but better than now and no more rust.

thats common knowledge btw.
torpedo tits rule btw.