Spent a little time on it again today. Straight edge comparison between good and bad sides told me I'm getting the lower edge at the bumper cut-out close to where it belongs. Definitely not off by an inch, still too bumpy to put a number on it.
I hit a high ridge near the original vertical crease with the shrinking disc and am starting to try and smooth the damaged area out. So far, the rigidity in the upper panel is holding... the oil-can has not returned. Yay!
Here's where I ended today... gnarly but I'm optimistic:
