I didn't wash mine as it was done when it was imported plus theres the issue of water ingress.
I used those individual ramps this year saves jacking up and down. But axle stands are fine, i did the whole car in under 4hours that included getting a wire brush and removing all the !Removed! and loose old stuff then applying new coat. It drives out moisture when you put it on so as long asbyou leave it to dry for 12 hours it should be all good. I'll see if i can find the pictures