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try a bit of Autosol (Supercheap & Autobarn etc have it) on a cotton tip or a pencil rubber to polish it out, take your time & see how it goes,
if it's heavier you might try going to a 2000 grit or...

Good to hear all is going well still Jay.

sorry I can't help with the steel choice but I as sure someone with the knowlege will chime in with some useful advice

have fun & I hope to see what...