My advice would be to add the spices after fermentation . Put them in a little muslin bag suspended in the beer and taste daily until you get the desired spice. If you add to the boil and get it wrong you are left with 40 pints of un drinkable beer.
My other advice would be to swap the horrified devils toenail clipping wheat for wheat Malt much better flavour.
Secondly if it is a Christmas ale why is it only starting at 1046 , it's Christmas it should be at least 6%, that's the law for Christmas ales