An RPQ = Request for Price Quotation.  Essentially a request for an activity that is not a generally available configuration.  By disk shelves do you mean DAEs?  If so, they probably could be reused - the RPQ would determine that as well.
Dear All,  I have a customer who is decommissioning DL 4206. Can we reconfigure DL4206 as a CX3 and use it as an CLARiiON.  Any suggestions are appreciated...  Regards, Prem 
Use DL4206 as a CX3