LX1 is furthest downstage, working upstage as the numbering increases. FOH position numbering for bridges, slots, booms, etc. likewise works away from the pros - bridge 1 closest to the stage, incrementing numbers as you move away from the pros. In non-traditional spaces - studios, for example - then obviously this doesn't necessarily apply, and there will quite probably be a space-specific system of designating lighting positions which will vary according to the way the space works. The fact that you've asked this suggests that you've encountered someone who's suggested that it should work the other way (low numbered bars upstage).... which I find quite astonishing, to be frank!