Installing BE 2014 Trail on top of BE 2010 R3

Hi

We have BE 2010 R3 running on our server (2008 R2 SP1) , we want to try the 60 days trail of BE 2014, but we don't have a test server to test on.

Can i just upgarde the existing BE 2010 to BE 2014 without entering a license to obtain the trail? or the trail cannot be configured on top of an existing BE 2010 installation wiithout installing the new license?

In other words - can i use the BE 2014 trail on my server that is already running BE 2010 by upgrading it to 2014 or i must configure it on a new test server as whn upgarding i must have the 2014 license?

We understand the risks of using the trail  for testing on a production server and not on a test server, we will take the risk.

Thanks