You want the same number of IBU as the recipe. Pellets typically have better utilization (transfer more IBUs) than whole hops, so you'll probably want slightly less by weight. I usually plug the recipe into bewersfriend and tune the hop additions to match the recipe's required IBUs. You can set...
There's a bunch of posts on this recipe talking about how good the spice tea is -- I would do it. Especially since the spices are tuned to be used with a spice tea, not in the boil. From what I've read, the spices are just right.
Water is heating right now, excited to brew this one!
I saw the Midnight Wheat next to the Pale Chocolate at the brew store and decided to give it a try.