I'd be tempted to NOT p2v them, but instead build new VMs (and storage) completely fresh (assuming the installs/configuration is documented) and set them up as a brand new cluster in the VM environment, that way your physical cluster stays online and you can do all kinds of testing on the VMs without affecting that. Using P2V for single servers is easy, but I've never had a P2V for a clustered server(with attached storage) go smoothly without a few issues.