Ford pickup rear fenders will 42 fit a 38 to 40 I heard they will fit with help whats needs to be changed
ALLSO They are different just above the running board . there is a dust shield that mount under the bed ,,the fender contours to this befor it bolts to the side of the bed . 38-9 have one bump ,,40 an up have two contour bumps ,,or maybe its the other way around , they can be switched, but you got to be good with metal mike p
'38-'41 is the same; '42-'47 is the same. '42 moved the spare to driver's side. They are different where they meet the running boards. Also up through '41 had the gas tank under the bed at the back of the frame and gas filler in the left rear fender. '42 and later has the gas tank under the seat and no cutout for the gas filler in the fender.
so the would it be was easy as just gettinh a fender patch panel where the fender meets the running boards