are the legs of the gen 2 performer steel.. i always thought they maybe aluminum...
proper way to repaint rusted metal.
sand all rust completely off, wipe down with denatured alcohol or mineral spirits. etc..
let dry completely.. i tend to take water after and wipe down again/ let dry completely.
then i use rustoleum high heat paint, which requires no primer/ 2 coats per oem instructions...
once you perform the prep.. follow whatever instructions are recommended from the paint can.
given the rust is @ the bottom of the legs.. dont worry about using high heat temp.. unless you are buying the paint.. as you may want to use same paint to touch up other areas closer to the kettle/ higher heat action.
if you have std paint laying around.. i would use that ..if only painting the bottom section of the legs.. you wont have much heat exposure in that area..
good luck