Anyone ever paint Aluminum Siding?

[Chief Roundup]

I have never painted aluminum siding before. I have several that I am going to paint. The current paint is pealing off in places and leaving that white transfer to whatever touches it.
Does the aluminum have to be "etched" before I repaint? What is the best paint for painting the aluminum? Should i use a paint and primer in one? I am going to pressure wash the painted ends of these homes to remove the pealing paint today and tomorrow. So I may not respond much during the day today. But any info would be appreciated.