What are the devices? Are they both phones? If so, you should be able to swap them without doing anything further assuming they both use the same type of SIM.
Yes, both phones. 1520 and 1020. The 1520 has a smaller SIM but I bought an adapter. I popped it in the 1020 and it showed a signal, but no data. I didn't try to make a call.
Figured I had to swap the IMEI associated with the SIM?
The problem may be related to the adapter. I wanted to do the same thing between my 920 and 1520 but many people on this forum discouraged me from using an adapter due to reliability and other issues.