It has to be a partial mash, because of the oats. So let's see, you'd have to be able to mash 4 pounds of grains at a minimum.
1 pound Caravienne malt
1 pound Munich malt
1 pound flaked Oats
12 ounces flaked barley
4 ounces chocolate malt
4 pounds extra light or light DME should work for 6 pounds pilsner malt.
Bring 8 quarts of water to 168 degrees, and add grains. Use two bags if you need to, to make sure the grains are loose. Stir well, and let sit at 150-158 for 45 minutes. Lift out grain bag and pour 170 degree water over the grains up to your boil volume. Discard grains. Bring to a boil, add the DME and bring to a boil again. Add the hops as directed.
If following the PM version you created earlier in the thread could you get away with only using a gallon of 170 degree water to "sparge" so as to make for a three gallon boil?
If so, how would you adjust the hopping, if at all?