SHC & PO deletion

Hi Friends,

I am working on Extended classic scenario SRM 5.0

I have created a SHC- 1000 and PO-2000 for the SHC -1000(as a follow on document)

Output type for the PO-2000 is triggered.(i.e mail sent to vendor)

I have gone through some thread which says we cannot delete a PO in SRM once output type is triggered?is this correct?

Now my requirement is ,

I need to delete the PO-2000 and SHC-1000(which has 4 line items)

what is the standard procedure/steps to delete PO & SHC in SRM ,so that no one should not use this SHC/PO in future.

Thanks,
San