I dug a little deeper and the 1929-1957 master parts catalog clearly states under group number
8.20447-51, 54-55 Panel (1st Ser.) pertaining to rear fender moldings. It skips years 52-53
There also was two different parts numbers for rear and front fenders, one number for
fenders with holes stamped out for molding bolts, one number for fenders without molding holes.
(Master Cat. does not show parts numbers for fenders that are stamped out)
Assembly instruction does show 54-55 1st front hole stamped fender part number and 47-55 1st. rear hole stamped fender part number.
Also the 54-55 1st front fender is different because they moved the blinker/parking light under the head light.
FYI