I did them pointing towards the bar that goes across on my 617. I believe thomaspin's DIY site (which I do have a problem with, because he stated an order for the valves which was different than for my car, and both his and mine are 617s) says to have them up and to the right. He says there is a wide range to the right in which itll be fine.
I like using the bar though, becuase this way all valves are measured with respect to a standard location for them to point, and plus I think thats why its there
JMH