the middle mark its white first is yellow second is white tdc and third is un colored your car will not start on the unclored mark make sure your timing mark is white so your top dead center (tdc)
According to the Gates website ( they make timing belts etcetera ) The 3.0 liter V6 engine in a 1989 Ford Taurus SHO has a timing BELT
1989 was .042-.046 gap
it is 7 degrees BTDC
The timing is adjusted by the three bolts that holds the injection pump. The holes in the pump are slotted.
The 1989 Taurus has larger headlights separate from the turn signal(corner lamp) The 1993 Taurus has more slender headlights joined to the corner lamp.
Ford Taurus SHO was created in 1989.
Taurus
Normally an engine this old that needs a new timing chain, also needs an overhaul. I cannot tell you in this limited space how to change the chain and gears. I suggest you purchase a Haynes, or Chilton's repair manual.
A 1989 Honda Accord has a timing belt.
For a 1989 Ford Taurus : ( 16.0 U.S. gallons / or the optional extended range tank which is 18.6 ) According to my Chilton's book
flywheels are not adjustable
Timing Belt