Not bad at all, it's ok it's not GM rust either LOL
I call that surface rust at the worst. Maybe a little sorta worse on that wheel well but that's still no big deal at all. Fame and all looks perfect to me.
If you would like to check out my website that has all sort of information especially for the T444E/7.3PSD engines check out www.PatrickTheSalvageGuy.com I've got helpful downloads and articles as well as a link to my YT for other how to videos mainly on the F series trucks.