iPhone Backup/Transfer only text messages

OK, I know this has been talked about, but I've never got it to work for me. I always ended up just giving up and starting over, but this time I can't, I have a lot of info in text messages I need.

If I

1)backup private>var>mobile>library>SMS>sms.db, then
2)upgrade my OS,
3)copy the sms.db back to the phone,
4)change permissions

I should be good right? I see there are new files in the SMS folder now -shm and -wal? I read they are something to do with iMessage maybe? And what about the Attachments and Drafts folders and contents? Can I just backup the entire SMS directory? Then what about permissions, I don't want to edit these on a ton of files.

Like I said, I've never been able to get my text messages transferred to a new phone this way, they will show up but I can't receive new texts after doing this. I want to make sure I know for sure what to do before upgrading to 5.1.1. I do want to upgrade because of all the tweaks and crap I've put on my phone, I really don't need to, but I would like to.

Last question, I don't use iFile, can I change permissions with an SFTP client? The reason I ask is, it aren't worked for me in the past either way.