^^IT MAY LOOK INVISIBLE ON THE FORUMS 
For anyone who has HBMAME setup in their systems, here is a monochrome logo to drop into the ~/retroarch/assets/xmb/monochrome/png/ folder.
HBMAME/MAME/MAME2003-PLUS all work great using this guide here: https://forums.libretro.com/t/howto-generate-pretty-curated-mame-playlists-the-easy-ish-way/5529