While a friend is welding the header collector flange to the downpipe, we decided to put he fenders on.
About five hours work, but decent result. We needed .750" of shims on each side where the rear of the fenders sit on top of the firewall. I've never seen that amount of shimming on any car I've worked on, but we did achieve proper alignment with that much shimming. Wow, it takes some convincing to get the proper profile of the fenders to match the doors. Those bottom shims at the dogleg really change that a lot, but judicious prying with a padded 2x4 was needed to move the fender as needed.
The black strips on the driver's side near the emblem is from Eastwood Rust Encapsulator that leaked through the holes when I sprayed the inside of the fenders. That is a really nice product--seeps into the seams very well.