Damper mark @ dot to dot ? ASAP

I'm building my 273. I've got the 1 piston at TDC. Cam mark at 6 o'clock/ crank mark at 12 o'clock (dot to dot) Put on timing cover and check the damper mark to )0.

((On my cover the timing marks are on the drivers side.))

Well the damper mark at TDC are 90* off., the damper mark is at the location for A PASSENGER SIDE MARK LOCATION. Whats the deal ? What am I missing . Never had this happen before.
Mind you I've just bought this truck, and it was rebuilt at sometime in the past.