First of all use some real heat to get the seized pin out of the bushing. . Then fabricate something in very close quarters. I found it to be a miserable small job unless one took off the fender. I did not.
Make sure to lubricate the other side as you will not want to ever do this again. The pivot pins are almost invisible but once you have repaired one of these my guess is you will never forget to oil them occasionally.
The original cause is not structual weakness. Seems the pin just rusts solid to a dry bushing. When you open the hood the bushing just rotates with the pin and tears out of the sheet metal. Or at least that was my experience.