Decommissioning a RHEV Storage Domain

I'm in the early stages of unpicking exported FC LUN's (virtual volumes) from a RHEV 3.5 environment. The target is to eventually remove the SAN unit providing the volumes.

Whats the best method to do this once the RHEV storage domain has been removed/destroyed.

I'm my experience, unexporting a device at the SAN layer seems to cause a panic at the RHEV layer as the host detects down paths, even if the device is not part of a domain anymore. Unpicking the multipath device from every hypervisor could also be troublesome as this is an arduous task manually, and a very dangerous task to script... and would have to be done within a short space of time as an "accidental" scsi-rescan would put them all back...

We have upto 12 hosts in each RHEV datacentre and hypervisors run RHEL 6.7 (not RHEV-H)

Wondering what approach others have taken to do this?