Pickup Rear Fender year?

[Mark Slight]

I've had this Pickup left rear Ford fender for some time, since I don't have a catalogue I'm having a hard time identifing the year. Can anyone of the Berners help, thanks in advance. Mark

 

[Ken Crans]

55 Ford F100

 

[cb]

1953 - 1956 f-100 and 1957- 1972 with a step side box.