Painting Mailbox Clusterboxes

Has anyone had any experience painting their old clusterboxes? We just purchased a park that has a nice set of old clusterboxes that work fine but could really use a fresh coat of paint. I have scoured the innerwebs trying to find a youtube video or DIY article on this subject but I have found very little information. I was just going to pressure wash them and them spray paint them. Just curious if anyone has every done this.

Thanks,
Jon

These seem nice: Individual Mail Boxes vs USPS Community Mail Boxes - #8 by Kristin