Did you figure this out yet?
IIRC.. either method works.
With both at 12 o'clock you are set up with #1 cylinder at TDC
At 6 and 12 o'clock you are set up with #6 cylinder at TDC.
Both are correct.
My method for finding TDC on #1 when working alone is quite simple.
1. remove all plugs (easier to manually turn crank)
2. Roll up some paper towel ( like a 3" cigar) and place it loosely in the #1 spark plug hole.
3. rotate crank clockwise (looking at the car from the front perspective )
4. if you are situated just right , you will be able to see the paper towel. When on the #1 compression stroke , it will pop out.
5. Continue rotating crank until the "0" marks line up on the harmonic damper and timing tab.