Didn't realize how much rot mine had when I got it.. First decision I made in deciding not to scrap the car was to buy a welder and learn how to use it. I didn't have anything as bad as what you showed on the frame. I did patch a few spots where a small side or bottom area was rotting( usually around an original punch hole, but the corners of the rails were still solid. Mine is staying slant 6. If I had planned to increase power much I probably would have cut a lot deeper.