Include MV45AFZZ: 

*------------------------------------------------------------------*
Form Userexit_move_field_to_KOMK.
* The one-off include file reference:
INCLUDE ZV45ZZ01.
endform.

Form Userexit_move_field_to_KOMP.
* The second one-off include file reference:
INCLUDE ZV45ZZ02.
endform.
*------------------------------------------------------------------*

In each custom include, you would then either add your own code (version 1), 
OR an additional list of includes (version 2), if necessary.  

Which solution you choose really depends on how many developers end up working on each function:


Include ZV45ZZ02:

Version 1
*------------------------------------------------------------------*
Move: xvbpa-kunnr to komp-zzkunnr.
*------------------------------------------------------------------*

Version 2
*------------------------------------------------------------------*
* Outbound Handling
INCLUDE ZV45ZZ02A.
* Inbound Handling
INCLUDE ZV45ZZ02B.
*------------------------------------------------------------------*