Having both trial and dev version of Telerik Reporting side by side is not possible, so you should have definitely uninstalled the trial one before installing the dev version. Then simply go to C:\Program Files\Telerik\Reporting Q1 2008\Bin (default install dir) and copy the assemblies over to your production server.
Currently differentiating between trial and dev version directly from the assemblies is close to impossible, so we would add "Trial" word to the description of the trial version of Telerik Reporting assembly to make this easier.
All the best,
the Telerik team