There are 2 options
In your 1st thread you did not want Equipment number. So that was the solution.
In the present thread you want to adopt the Serialized Material and Equipment route. If it is so you do not need the code changes suggested in 1st thread.
Ours is the 1st method, but we get the Equipment fields, we do not use.
Your problem has lot of content in scn. Search Google with string such as 'Equipment and Serial number in Refurbishment' . This issue was discussed in few threads. Also because this thread ran quite lengthy you may close by marking Assumed Answered or so. Try it on yourself by search and research and if needed start a new thread. At one place I read about the Business function I referred below (LOG_EAM_ROTSUB).
Bye