These are two different cars we did at our shop. The tubs are 14" wide and made out of 16ga steel. We could have made them narrower, but wanted to try it out going straight up from the frame rail. Some will like, some will not. There really is no wrong way of doing this as long as your gaining space in the wheel well.
Unfortunately the way our site is setup, I cannot copy a picture link address. I still need to add updated pics of the black hatch. It's just about finished and ready to drive home. Sorry for the linking, mods can delete if they see fit.
Jays two4oh!
Devins 240