66C in my book is standard mash temp!
The lower the temp you mash at the less higher order sugars you get.
This should then ferment out to a lower gravity, drier brew.
If your after a really dry beer you could also add pilsner powder, in the fermenter, it won't give you a pilsner just a dry beer, as it contains enzymes that convert complex sugars that are not normally converted in a traditional mash situation.
You will get a very thin dry beer with not much body, you can get it Here or your local HBS, None of the forum sponsors seem to stock it though.