Yep, that's right. If your sure that the 1Tb size is that of regular 2.5" HD's. Also I delete the game data before I Backup. On my system its a few hundred gigs, on yours it only may be 50gigs. But the less time your system is left on the better. I have seen 70gig restores take 10 hours. But Then again it was on an older FAT and the hard drive was failing. I delete all irrelevant data anyways so I have a restore image of my PS3 before I go to a higher capacity hard drive. It has my saves still and some other stuf that would be hard to replace.
One other thing, before you start the backup/restore I would do a back up of all your saves to an external or thumb drive. I would hate for it to fail and you lose your saves, seen happen and it's happened to me. That way, you will have a copy of all the saves you can transfer from one system to another. there may be some that you can't backup to your external manually, but those will carry over in the restore, hopefully .
CECH2501A-750GB Rebug 4.46.1 / CECHG01-250GB Kmeaw 3.55 / 2TB External / PSPGO 6.60 PRO-B10 / PS2 v2