Curious what the reasoning was for that decision? Save for the last pic of the rot in post #37, was there damage to the inner structure? No matter now though, all new and presumably straight.
Were the inner seams primed/coated before the new panels were welded in? Installing new quarters had to have made replacing the trunk easier but on the surface replacing the entire rear clip over a patch seems like a lot of extra work. Or maybe not. Perhaps being able to access everything takes less time and nets better results?
I ask because I'd like to de-trim my Coronet 440 and make it into an R/T. Removing the car-length trim strip and rear quarter badging leaves a lot of trim holes to fill, some of which can't be easily accessed from inside. When you think about it, might just be easier/less time consuming to replace the whole quarter. Starting with a solid panel would certainly require less prep work after filling the holes.
Also, don't know if it was mentioned but was this a vinyl top or paint?