Replicate ECC Product Hierarchy to SRM?

Dear SRM Experts!

We are running SRM 7.0205 (SAPK-70205INSRMSRV), integrated with SAP ECC 6.06 (SAPKH60604), and have currently NOT activated “Hierarchies for Product Categories” in SRM (IMG activity - SAP SRM - SRM Server - Cross-Application Basic Settings - Activate Hierarchies for Product Categories, etc)

We are, however, using Product Hierarchies in SAP ECC (MARA-PRDHA), and have already replicated materials to SRM.  A few questions:

1. If we activate “Hierarchies for Product Categories” (above IMG activity) in SRM, does this allow us to replicate ECC product hierarchy to SRM? 
2. If so, how do we replicate the product hierarchy from ECC to SRM.  Do we use R3AS middleware transaction?  What load object is it “DNL_CUST_PROD1”)?
3. Once it is replicated, where is the ECC product hierarchy represented in SRM?  Is each SRM material (product ID) linked to a product hierarchy (similar to ECC field MARA-PRDHA?)
4. If we replicate ECC product hierarchies to SRM, will it have any negative impact on existing materials that have been previously replicated?  I see in the IMG activity defined above, it says "These hierarchy functions should not be reset once they have been activated."

Thoughts?

Cheers,

Aleem