sprint, relocking and returning

[ipclark11]

couldn't find a complete protocol for returning a damaged unit to sprint repair center. My chrome is very cracked and scratched and this was enough to replace my last unit a few months ago (had stock sprint rom so this wasn't an issue). My question is do I NEED to relock and restore old rom BEFORE they examine for replacement eligibility? I understand when i bring it back the second time when my new phone arrives to be exchanged it should be relocked/stock sprint rom, but (just to be brutally honest) they are not the brightest bunch at the repair center by my place and my phone usuallty takes AT LEAST a full week until it arrives. I guess i'm saying do they check the rom information out because it seems to me they usually just look at my phone physically for about 2 minutes then say well call you when your knew one arrives.... I just don't want to reclock/restore, bring it in, get home put MR5 back on it for a week, add my old programs/contacts, wait a week, relock/restore, pick up new phone, then have to flash MR5, etc...i hope i'm being clear enough. thanks in advance for any help