Maccrae

So I am unable to run any n64 game in launchbox because I cant pick the correct core from retroarch. I have downloaded the 2 available cores from retroarch (Mupen64plus-next and ParaLLEI 64) but in Launchbox the core is set to Mupen664plus-libretro which is lists as missing core. I try to change the available core in the dropdown but neither of those are there.