Adding Bongo Sound to Drumset

Hello,

I am working on writing a multiple percussion piece and I've been able to get a majority of the sounds I want except bongo. Does anyone know how to add the bongo MIDI to the drum set? I know that MuseScore already has it.
Also, does anyone know how to delete unnecessary instruments from the drum set (cymbals, snare, etc.)?
I'm not sure if it would be different from Windows but I'm working on a MacBook