Best way to upgrade old FreePBX /Trixbox systems to current release

I’d like to migrate and old Trixbox server to a new machine equipped with FreePBX’s last version.
I’d like to retrieve all current configurations (trunks, outound/inbound routes, extensions, and so on…), in the best and easy way.
Moreover I wouldn’t upgrade or touch in any way the current (old) Trixbox production server to avoid possible and drammatic issues.
Have you any ideas?
Thanks in advance

If your Trix is running with FreePBX 2.9 or later you can use this method:

If not, side by side cut and paste, and exporting the old and editing for bulk handler on the new.