so, I'm wondering if anyone has a solution which I do not have to move the data out of it.
Some users have reported successful single disk to RAID1 conversion without loss of data,
other users have reported total loss of data. Which experience are you going to have? No
one knows for sure.
Without a backup you are taking a risk, regardless of whatever anyone tells you.
With a backup, it really doesn't matter how you complete step 2 (from post above)
you can always get your data back.
So the questions you need to answer...
"How much is your data worth to you?" (more than the cost of a backup?)
"How painful would it be to loose all your data?"