Assuming it's a supported driver type (we don't do EXE's for instance) then you could simply create the folder structure necessary for the drivers (along with the INF file and all that) and then drop the folder into the file system. Then launch the console and see if it picks it up or fails again.
The simple truth is that when you add drivers via the console, we build a sub folder, copy the files in, and extend the manifest file. If you copy the files in manually, once you launch the console piece, the manifest file is recreated anyway, so if that works, the net result is identical.
Generally speaking. I've never had a complaint about it yet. :P