U can find the correct rotation by "bumping" the key switch & watching the fan..in MOST cases.
Its VERY important that u go in the correct rotation because if u don't, you'll add "slop" to the timing..
IF u go in the correct rotation, it reduces the gear-train back lash..{slop}
Good luck
Its probably best to remove the valve cover TO BE SURE your on the right stroke.{compression}
U have to remove the injector lines ANYWAY.. so do it 1st & remove the V. cvr.
{TIP} The engine is WAY EASIER to turn without the injectors in it..