I initially started doing the same by splitting the inner fender and bending it up, but didn't like all the gaps and it didn't fold up cleanly. I ended up cutting it out and butt welding in filler panels. I didn't see a lot of info on how to do it, so created videos to share with anyone looking to do it. Link to my channel with the videos is below and documents the whole process.
https://www.youtube.com/channel/UC1YCL-94VAUmAG_ciYiMtLg