I recently had a Widmer Brothers Nelson Imperial IPA. It was magnificent. Here is what their website says about it.
70 IBU
8.6%
Original Gravity : 21 Plato
Malts: 2-Row Pale, Carapils, Caramel 10-L
Hops: Alchemy, Nelson Sauvin, Cascade, Willamette
This would be a great beer to try and clone.