I think I found you the group and part numbers for the inner fenders, I am still not 100% certain if this part is shared with GMC, I suspect is would be.
Group 8.153 Skirt, front fender
47 COMM. left, front 3683075
47-53 COMM. right, front 3683076
48-53 COMM. left, front 3687381
47-53 UTILITY (exc. COE) left, front 3683081
47-53 UTILITY (exc. COE, SBC) right, front 3683082
54-55 COMM. (1stSer.)(exc. D-D) left, front 3700513
54-55 COMM. (1stSer.)(exc. D-D) right, front 3700514
54-55 UTILITY (1stSer.)(exc.COE) left, front 3700503
54-55 UTILITY (1stSer.)(exc.COE, SBC) left, front 3700504
For some reason the 47 driver side 3683075 is special, but eventually 3687381 replaces it in the parts catalog.
Sources:
Master Parts Catalog 30 June 1952
Parts and Accessories Catalog P&A 30 March 1957
-s
