Stroking a 318 to a 390

I've just recently acquired a low mileage '89 roller cam 360 with the stock cast pistons at .125 inch below deck. Since we're talking about going all ghetto, would the stock pistons have enough material to mill off .100 off the top on the valve side and enough off the bottom (if necessary) of the pin boss to fit a 4 inch cast crank?