Here's a mock up of an extension tacked together. The rear flows better as it does not dip down as it meets the bed side. I was expecting this but it does not really concern me. I still have to fine tune a lot of stuff. Mold metal towards front and rear bottoms of fender to fill the gaps, adjust some of the tacks straighter. I think it will work out OK!
1970 Chevrolet C10 Grandpa's -- My first truck -- In progress to shiny Follow the build in the Project Journal 1950 Chevrolet 1-Ton Dually "Ole Red Girl" In the Stovebolt Gallery More pictures here 1951 GMC 9430 1 ton dually--Shiny! | 1972 Chevrolet C20- Rusty- the puzzle box lid for the C10 | 1962 AMC Rambler American- my wife's Parts trucks- 1951 GMC 9300 | 1951-GMC 9430 | 1951- Chevrolet 1300