01-22-2013 02:26 PM
Hi and Welcome to the Community!
Assuming that the 8520 contains nothing you need to keep, then if you used the Desktop Software to create the backup files from your 9800 to your computer, you can again use it to perform a restore to the 8520:
If the 8520 does contain data (e.g., contacts, calendar items, etc.) that you need to keep, then you instead need to extract from the 8520 that data to your computer, extract the same data from the backup files from the 9800, merge them together (on your computer), and then finally import them back to the 8520.
If these files are just files (e.g., pictures, videos, etc.), then you can use Mass Storage Mode to copy/move them to the BB: