Having read Zimbra Downloads FAQ: Phase-Out of 32bit document I wanted to be very early in this process.

I currently backup my ZCS zimbra 2 ways.
1 - gzip tar ball
2 - rsynch to another machine

So basically, I have the 32bit backup of zimbra.

Can I then just install the 64 bit
move the installed /opt to /oldopt
untar or copy over files from backup to /opt
do the permissions thing on directories and I'm all set

My worry is that I won't be true 64bit. Am I wrong on this ?
What's the proper way to do the migration ?

I know what didn't work
Going into 32bit machine and exporting the 5 accounts as tgz file and re-importing into the new 64bit install. Basically, it didn't come back with all the files from briefcase and other things.

Any ideas guys..TIA