Ok, I gave up on the stock bolts. I couldn't find 8mm well nuts (sex bolts, barrel nuts, etc) that fit through the eye bolt hole. So, I got some corner brackets and drilled them out with a cobalt bit to 8mm, but even as flat as they were, they wouldn't fit over the rear bolts (the depression in the fender is the only reason the stock nut fits on there).
So, I finally did what Toncka told us to do in the first place: replaced the bolts. It was easy to find ones that were just a bit longer (about half an inch). It took a little arm contortionism to get them back through the fender from the inside, but it was doable. So, long story short, I went back to the eyebolts (with fender washers between them and the fender rail), which worked like a charm with the longer bolts.
If I had done it in the first place, I could've saved myself several days and dollars worth of effort and materials.
Some pics...
