I'm trying to model my first car in blender. I started by creating the front wheel arch and then duplicating it and scaling it to -1 in the Y direction to create the rear wheel arch. I then continued to extrude out the side of the vehicle from there.
Now I want to create a bridge between an edge towards the front of the car and one towards the back so I can model the area above the windows. When I select the edges and create a bridge (W > Bridge Edge Loops) I end up with a twist in the bridge:
I assume the edges have inverted Y axis orientations caused by me when I mirrored the wheel arches by scaling -1. I have tried recalculating all normals and playing with the Twist setting in the Bridge tool but I cant create bridge without the twist.
How can I fix my model so all faces, edges and vertices have the same Y axis orientation again?