SEIZING FSMO ROLES QUESTION

SEIZING FSMO ROLES QUESTION NOT TRANSFERRING.
Lads Just to double check as Ive never actually seized all FSMO roles in the past, but the way things are going I may have too.

The main dc with all 5 fsmo roles has gone bang, hard drive problems, was in a raid had 3 drives go at once for some odd reason, had HP in looking at it etc etc, anyway new drives being put in now, 2 logical drives with 6 physical hard disks.
I re-built identical as the old one kept it out of the domain etc etc.
Went into ad restore services and restored via Veritas 10, however on reboot I received the same error as before when the hard drives went down, I think this COULD and its a big COULD be due to it being the very latest backup of sys state being used and POSSIBLY having what ever corruption in it.
Anyway Im now rebuidling again as I type here to reinstall all service packs etc and try an earlier backup of sys state.
IF THAT DOES NOT WORK
Im going to have to go with renaming the server differantly and bringing it up as a differant DC.
My question to those who have seized all fsmo roles in the past.
What problems do I need to look out for as I have 2 current DC's running at the moment which I can put the fsmo roles onto and then bringup the new dc and clear ad manually of the old DC.
Hopefully I do not need to do this but on the off chance I have too I'd appreciate the benefit of your past experiance, I have all the documention etc but these docs dont always include the small tips.

Thanks

Roy