Is a secondary mesh for just the arms required for UFPS?

Ah, thanks a bunch for the (very quick) reply! I'll check out this tool, I thought it was just for hitboxing, had no idea it was also for doing this.
 
One more question if you don't mind, I just used the FPS Mesh tool, it still keeps the whole skeleton instead of just the arm bones. Would I use UFPSDemo anim controller?
 
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