Confusing, isn't it?!
So, if you're looking at the bike from the left side (facing forward) and turning the crankshaft forward with the crank turning tool, the crank turns anticlockwise, as will the rear wheel, if it's in gear.
Going round to the right side looking at the belts, when the engine is turning forwards, the drive shaft pulley rotates in the opposite direction to the crankshaft and at half its speed. To the observer on the left side, it will still rotate anticlockwise.
So, turning the crankshaft 270° anticlockwise (viewed from the left), will cause the drive shaft pulley to rotate 135° anticlockwise (viewed from the right).
If you look at this video from Brad (at 4:26) he sets the vertical cylinder to tdc by rotating the drive shaft pulley anticlockwise until the timing mark is pointing forward at 3 o'clock i.e. 135° from the horizontal cylinder's base position at between 7 and 8 o'clock.
Hope that helps!