Need to add fields into VFX3 output using Z program

Hello All, I have to add some 6 fields into VFX3 output which comes into ALV form.So shall i copy the SDBLBDDL.(VFX3 Program) and create a new z program and add field or there is any other solutions, as user want to do not add anything in Original VFX3 program, he want to use new z program which is copy of original one and make changes there and create a new tcode ZVFX3, but my concern only regarding ENHANCEMENT which is used in original program,Is any impact on ENHANCEMENT which has used in original program..so that i create a copy of original one and add field into structure. Please help me out. Thanks Sankil