You can use the existing loadmodule as input to the linkage editor and specify a REPLACE parameter to delete the csect that is no longer required (see manual MVS Program Management: User's Guide and Reference)
As suggested, the REPLACE control card causes the named csect(s) to be deleted from the load module input to the linkedit step. Any REPLACE'd csect(s) in the SYSLIB concatenation of the linkedit step will then be used in resolving the reference(s).
Any REPLACE not followed by (replacement) will be checked by the linkage editor whether that Csect is in use, if not it is deleted, plus all other NAMED csects inside the aforesaid loadmodule. Used that way REPLACE performa a spring clean.
The scope of the REPLACe covers only the INCLUDE immediately following.