Remove paint fron sandstone steps

[ManSizedRooster]

Hello

I have some old sandstone steps that have been marked over the years with paint spots when the house was repainted. I've used a power washer to remove the general dirt and alge but the paint won't budge. I tried paint stripper and spirits of salt, but the paint doesn't react. Is my best bet mechanical removal? And what would I need for that?

Cheers

MSR

[chriscba]

A grinder with a wire brush attachment