Game BootLocations

So, I was wondering. I use RPCS3 with Launchbox, and have the emulator set up within Launchbox's emulator folder. HOWEVER i use a separate (BIGGER) drive to hold my games. how do i go about using this other drive to hold my PS3 games and keep RPCS3 in its current location?
(I have a mix of Disc images and PKGs) I couldn't find any threads on game booting locations...