sosman, that sounds right to me.
Hoops, I was looking at doing 20% maize, slightly less than yours, so I'm thinking I might give it a crack.
warren, too late! I've already got the grain cracked and ready with 1.5 kg weyermann pils

. I do have 500g of wheat in there too, which will boost the diastatic power.
And if the grain bill and my motivation for using 20% are sounding odd here, I put this recipe together meaning it to be a partial, but on the way out I started thinking I'd rather just do a mini all-grain. The recipe is meant as a base to test out some home-grown chinook hops, yeast will be 1272 (American Ale II).