Removing UVs from a uv map?

I’m trying to split the UVs of one mesh between two different UV maps; as in head and torso on one, legs and arms on the other. Problem with this is both UV maps appear to have all the UVs of the mesh on them.

how do I remove the UVs I don’t need from a UV map?

oops, this is prolly wrong forum. Shazbot.