yes, going to kinda do like you did, maybe a little different, planning to cut the top of the cowl piece off behind the wiper arms and replace it with new from the part I ordered. Initially I was going to fab it up, but just too many curves there to mess with.
Actually if you look closely you will see that those ridges around the wipers end about 3 in. from the back edge of the top of the Cowl panel. Yes the back edge is curved but it is flat. We did that whole back edge in about 4 sections. We used poster board to make templates to get the curve right.