RE: P40-E 60 size ARF problems.
Wait before you do...
You have nothing to loose by doing this...
You could CAREFULLY cut the wings apart on the epoxy line.
You will have to either use a fine coping saw or similiar saw, or something like a band saw, that is capable of making a clean cut through the material. The finer the better, but it will take longer to cut.
Do NOT pry the wings apart.
Once you've done this you can then sand until you get the right dihedral, then drill out any dowls and insert new ones, and re-glue everything... Consider also adding a couple of CF rod pieces too.
I've done this with a wing I once screwed up, and I've had no problems.
It's cheaper than ordering a new wing set.