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The firing order is 153624
As for the timing it can be any number of different settings because of a Marine aplication They somtimes had vacuum advance sometimes not.
I would advance the timing and then slowly retard it (under a load) untill just before the engine starts to ping.
Don't forget to set the point dwell before attempting to set the timing.
1: Inline six cylinder enginesFiring order: 1-5-3-6-2-4Distributor rotation: clockwise
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