That's a lot of agave. Where did you manage to get raw agave nectar? The only place I've seen that was in Mexico. The processed agave (agave syrup or meil de agave) is pretty available. In a 5 gallon batch I would use 16oz. for additional fructose. It doesn't add a lot of flavor from what I could taste. The raw agave juice has a lot of flavor although I'm not real partial to it. Good luck with the recipe.
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