The 40 pickup fenders have a different flange than the car does as they attach to to the body. The flange can be bent on a car fender to to make it work on the pickup. It will take some work but it can be done. I have also heard that the pickup fender is a bit shorter. I have not confirmed this though. I need to drag out my sets and do some measuring to see this. As far as 40 to 41 pickup fenders they are the same no difference. Good luck