1972 Canadian H-Code 340 Dart Swinger Special Resto - Finally started!
Appreciate the sentiment Anders, hope it helps anyone that wants to tackle some of this work on their own cars.
Decided to abandon going with lead on my sail panels, I haven't touched any lead for 30+ years and figured I'd likely end up with a mess so I went with All Metal. Since I welded the seam solid and I don't intend on doing any body twisting launches, maybe a tire chirp "lol", I'm pretty sure it will hold up fine.
Now what might seem a bit shocking for some after seeing all this pristine sheet metal the reality of getting a dead straight body takes either gobs of very expensive hight build primer or skim coating all the sheet metal with a high quality "don't skimp here" body filler and long boarding it off. As you can see by the filler that's left behind on the AMD panel although pretty nice aren't dead straight and for that matter either are my original panels. The centre of the door had the crease in it so that was going to have filler in that area but you can see that the top third of the door as well as the bottom third, that never had damage, although pretty thin also have low and high areas that are reflected in the filler left behind. If you notice the amount of filler on the quarter panel pretty much matches the amount on the original areas on the door. The transition from the door to quarter needed a bit more filler since the fit of the AMD panel particularly this side left a bit to be desired, the body lines were good but the levels between the two weren't as good as I'd hoped for. The left side was somewhat better so it should need less filler. Going this route should reduce the amount of high build primer by a lot.
For those curious on how to prep the steel for the skim coat the method I used was running my long board with some 80Grit paper up and down the panel so I provide a good scratch for the filler to grab onto then wiped it clean with some gun wash thinner or a degreaser. You want to lay down a thin smooth coat of filler and I'd suggest going easy on the hardener so you don't have to rush.
I broke out my wide drywall plastering knife which worked pretty at laying down a thin smooth coat which makes sanding a bit easier.
The weapons of choice needed to get a dead straight job, a tip for novices when sanding your filler off is once you start to see the steel approaching its time to start changing to to your finer grits and once the steel starts to break thru you'll want to stop sanding there any more since you've achieved level and flat and anymore sanding will just reverse what you accomplished and will begin lowering the areas around the high spots.