That's pretty typical rust. I'm kind of surprised they found enough clean metal to make the lead stick.
Patch panels are available to fix that mess, but it won't be easy, as the panels need to be tweaked to fit correctly (the worst being the inner cowl panel and the inner-to-outer cowl panel.)
You can browse thru my photos (link in my signature - starting at the top of page 3 and extending into page 2) to see where I did the same type of repairs. I replaced both front cab mounts, floor, inner, outer, and inner-to-outer cowl panels.
Good Luck
