there are at least 3 different timing mark positions... depending on the year...

12 o clock.. 2 o clock and around 2 30 for earlier motors..

but the bolts that hold the pulley to the damper.. one of them is always lined up with the keyway..

the keyways in both of these dampers are aligned..

you can use the adjustable knob on many timing lights to dial in i think its 30 degrees you need to add..






the biggest mistake is getting the distributor in 180 degrees out..

this is the reason... with the cam gear mark down.. the cam is set to #6 firing.. with the cam gear at 12 o clock the cam is set to fire the #1 cylinder.

two turns of the crank to one of the cam..

easy way to find compression on the #1 cylinder. only have a spark plug in the #1 cylinder.... slowly rotate the crank.. you will feel the compression building.. then bring the timing mark up. if you look at the bolt pattern on the damper.. you will know when its close to tdc..