MSD 6AL ignition box

So I got around to playing with this last night - connected the blue/brown wire - still not spark. I checked the voltage across the trigger wires during cranking and wasn't getting anything so I figured it must be the trigger. I checked the reluctor gap - way too big!! Reset that and voila - beautiful spark. Not too sure how the gap opened up, but the screw holding it down is very tight now.

Thanks for all your help guys,
Bryan.