Align bottle in brackets so that the valve outlet is pointing downward to the mounting surface (see illustration A) and tighten the bottle bracket bolts. NOTE: This is VERY IMPORTANT
so that the internal siphon tube will pick up liquid nitrous.
I get the whole mounting it with the outlet pointed down. That makes sense. I Can also see why you might want to mount it facing the front of the car. There would be a straight line instead of a bent line....i think most of htis only matters when ur low on nitrous