Well i know you pretty much have to be under the car to get a ratchet on the crank pulley bolt. I think its a 19 mm bolt. You probably only have to turn the crank about one fifth of a turn. I think there is a little cap you take off on the side timing belt cover, below the motor mount, that is where you will find the bolt for the tensioner. Take a look at this pic and the tensioner bolt is pointed out.



*edit* Not to confuse you but i say one fifth of a turn of the crank shaft, because you most likely will not be able to see the cam gears, because you might want to keep your valve cover on. In the picture it shows the valve cover off so that you can see the cam gears and rotate until 3 teeth move, you know.