You also have to consider that grain bed is going to be fairly stratified so you measure 151 in one spot - it could easily be 149 an inch up (just making an example). So you may want to come in a bit higher to start if you're looking for more body. The lower you get the more fermentables you're creating and you'll get that dry beer that's harshly bitter with no maltiness to back it up.
Good luck!