Hi Shanky,
It should be fairly easy if I understand the requirement correctly. My way of handling this would be,
1) Create a repository for your SAP ECC system.
2) Run the job wizard and navigate to the job templates folder and import "ABAP Initial load" job
3) Disable the passes which are out of scope for you. For your requirement, "ReadABAPUsers" and "WriteABAPUsers" should suffice, but if you want roles assignments etc along with it, then you can keep further Read* and Write* passes enabled. Optionally, you can delete the unwanted passes so that your job looks neat.
I would 1st run the job only with read passes, and check the temporary table if all good. Then would write only few users to IDM by delimiting the SQL using 'Top' command as in "Select top 2 * from sap%$rep.$NAME%user" (you can use any other method to select only few users) and check for any issues or if the result is as expected.
If the above steps doesn't help you, then let us know the precise information you are looking for.
Experts, please correct me if I'm wrong somewhere.
Kind regards,
Jai