I fixed the mis-aligned windshield wiper hole in the wooden header.
I went through all the old rusty nails and bits of anti-squeak I saved when I took apart the header a year or two ago. The header is complicated: there are lots of nails, and there are also two other metal pieces that run across the top of the windshield opening. Hopefully I will get the header nailed and soldered in place over the weekend.