Sounds like the top wing will need to be done in 3 parts due to the dihedral.
The reason for laminating the wing is to get the cambered shape with less sanding. One could use a single thick sheet of styrene and sand in the wing profile, but I choose to do less sanding and get the camber by laminating thin sheets (five 0.020") together, taping it over a round object. I have a glass jug that I use. The picture below shows the plastic sheets taped to the glass jug while curing. Try to avoid air bubbles between the layers.
I tried the Gorilla glue (polyurethane based) in the picture, but it didn't work. I use liquid styrene glue to laminate. Apply thin layers with a brush - too much will make the styrene too soft and it won't be sandable (learned from experience).
After curing a couple of days, untape the sheets and trace the wing profile onto it to cut it out.
For the wing rib detail, I emboss the ribs on 0.010" styrene sheet and glue on the top surface, like laminating the other sheets. Here's a pic of the skins.
Here I am gluing the skin on the top surface of the wing. Using the air inflated bag ensure even pressure across the entire surface without messing up the embossing.
Hope all this makes sense. This is why it takes me 6 months to complete a scratchbuild!
Again, this is just my method that has worked for me.