Skip BFG, and go straight for SGMiner. It's built and designed for scrypt GPU mining, and already has this feature added. Best part is you don't have to build it, as there are already pre-built versions floating around. Just check the official LTC forum for download links.
I probably will skip it (sorry nwoolls) but doesn't mean I won't look more into it later on.
What else should I know about sgminer on windows? I just had cgminer to play with.