In the early C4C days, I seem to remember that one had to scope in integration with ECC/CRM at the very beginning of a new C4C project. Activating this integration at a later stage (after data had been created in the system) was not possible.
Over the last 2 years I think I read somewhere this behavior is not true anymore. You can activate the integration at a later stage.
Can anybody confirm it is now possible?
This is a bit complex scenario. To my knowledge, technically it is achievable. Scoping is modifiable at any time. You can activate the integration scoping. the problem is only with your current production data.
But there is no standard way from C4C to support this.
we might to do lots of manual activities and workarounds.
Deleting the data is not possible in C4C.
My thoughts about this option.
As a work-around you can first migrate your data into ECC or CRM using download the data in template and upload it(before integration) and validate the data migrated data in ECC/CRM. Once this is done. Then we can request to decommission your current existing C4C system and request for fresh tenant with scoping copied(if you have multiple C4C systems you can copy from one of your active system)
Once this is done you can do the initial load of your old data from ECC/CRM to C4C(which you copied from your old C4C - ECC/CRM). Then you might have to do some manual activities for ID mapping etc.
As I told this is really critical decision and requires lots of risk analysis before this move based on your business. I don't see any much difference between initial setup of C4C and this approach rather it has more work.
Option 2: If you don't want to decommission the C4C tenant. Then enable the integration & download migrate the master data using the template and do the ID mapping manually for all the new ids generated in ECC/CRM in C4C. in this case we may have some issues with transnational data. This can be moved using below mentioned development option.
1. All the data migration(download template) is not supported, for Eg. There are still industry specific data download is not available. In those case it might require some custom SDK development/web service to migrate the data from C4C to CRM/ERP.
2. Available risks in data migration depends on the which industry solution you are using.
you can check all the supported data migration by default in 'Mass Data Maintenance' work center.
I will add some more information if I get.
Hope this is helpful