If the timing mark is lined up with the "0" or TDC mark on the timing tab, then yes, the engine will be at TDC on cylinder #1. The problem is that if you go solely by the timing mark you haveonly a 50% chance of being at TDC on the compression stroke.
To quote Reed

#1 & #6 are both going to be at the top at the same time, so watch the valves to be sure you have #1 at compression not #6 (they are 180 degrees off each other)

Richard

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