It doesn't matter all that much - you just don't want it to be at the same location as the rising edge of the crank tooth.
I detailed it in my (now resurrected) E30tech thread:
I think I recall saying I was trying to line it up with the falling edge of tooth #14.
I detailed it in my (now resurrected) E30tech thread:
I think I recall saying I was trying to line it up with the falling edge of tooth #14.