I think I have a recipe for Buffalo Bill's Pumpkin Ale. Looking at the beer, it has a low IBU (11) and uses Nugget hops. The brewery also says they use only Pale and Crystal malts (60L) so I came up with the below with Beersmith. Looking at this it is obvious where I went wrong, way too hoppy and too many grains. I hope to brew this recipe this coming weekend and can let you know how it goes.
I will say my original mellowed quite a bit and has become quite tasty, but nothing like Buffalo Bill's.
9# Pale Malt
1# Crystal Malt (60L)
.5# CaraPils (give it a little more body)
3 - 29 oz cans of canned pumpkin in the mash (Libby's)
.25# Rice Hulls
.5oz Nugget Hops (15 min)
1 tbsp Pumpkin Spice (5 min)