Custom Part Number for routing pipe.

Currently when I make a routing assembly, the bom fills up with a standardized pert number that seems to be created on the fly. Is there a way to edit this? Currently when i pick say 2' schedule 40 pipe it gives a user defined  part number as 3 in, schedule 40 for example. I want all 3 in schedule 40 to have a part number of 012345.

SolidworksRouting