I will tell you this , there is a pin on the camshaft,that pin must be covered by the washer,this very important because the pin can walk out of its position and then there is nothing to hold it to proper alignment with the gear/camshaft.
I had a moronic machine shop that assembled the engine before i could do a final inspection,well they put to small of a washer on the camshaft and yes that pin walked its way out until i was on the track and sure enough every thing shut down since the gear/timing chain were no longer on the engine, there was a quiet breeze at about 80 mph and i knew something was wrong, and yes it trashed 4 valves in the process and they were edlebrock valves special to the alloy heads, so make sure you have the RIGHT parts!