Installing PVSCSI drivers

Hi

I've an issue trying to use paravirtual SCSI interface for Windows VM.

I'm modifying a windows 2008 R2 Template and trying to install the PVSCSI driver from the flp image but got an error that the installation method isn't supported .

Can anyone help me ?

Also , what are the steps to modify existing VM to use the PVSCSI driver interface  ?

Thanks