Hi, I'm trying to get a '74 550 I bought a while back running, and have not been able to get any spark. Just to be clear, a 500 motor was just swapped in as the original had a broken timing chain. All oo the electricals seem to work, but there is no spark; plugs are brand new, points are clean and properly gapped, battery good. I just took apart the kill switch thinking that the connections might be corroded, they were a bit nasty, so I roughed them up and cleaned them a bit. Unfortunately, I can't quite remember exactly how the thing goes back together, does anybody have a pic of one that has been opened but not taken apart, or perhaps a scan from the shop manual? The Clymer is of course no help in this department. So say I get this back together properly and still get no spark, what's next? Coils? How do I go about testing those, and will my spares form a '73 750 work? Thanks a bunch.