DIY floor pans.

K.I.S.S. there's always my pawlosophy in this situation. I would do it one piece at a time. Even in the top right corner of your Square there I would 45 that a little bit and take a little less out...
I'm having an awful finding sheet metal every place I find it wants 90 plus shipping. There was one place the shipping was like 500 bucks haha freaking crazy even summit racing who normally has really good shipping prices is 90 bucks shipping 2 pieces is gonna be close to 200 bucks if I cant find it cheaper than that I will spend a extra hundo and get the prefabed ones