OK, I boiled it up yesterday and set it to ferment in the carboy.
I based the recipe off of a LHBS Scotch Ale; I'll post the specific recipe later when I have it to hand. I did the basic steep+extract method and a full boil using the grains provided:
5 gallons water in the main pot.
2 or so in a steep pot.
Steeped for 60 minutes; the temp climbed a bit more than I wanted it to, but not severely. Pulled the grain bag and poured the resulting wort into the main pot which was heated to similar temp.
Brought the main pot to a boil, then added DME, then LME (slowly, so as not to scorch, while stirring vigorously). Added hops at 15 minutes, let boil for 30 minutes, then added roasted pumpkin flesh. Since it was cold it brought the wort temp down enough to lose the boil, so I brought it back up and let it go for another 30 minutes, then added 1/2 tsp each of fresh ground nutmeg, cinnamon, allspice, and ginger. Let it boil for another 10 minutes, then added the Irish Moss and did 15 more minutes. Total boil time was about 90 minutes, although stove-top time was longer due to losing the boil in the middle from the cold pumpkin.
Here's the wort in my 32-quart pot:
After the boil I put it into the sink and ice bath, took about 30 minutes to cool. I tried to use a racking cane to move it to the carboy but the pumpkin had other ideas; kept clogging the racking cane. So I moved on to pouring it with a saucepan into the carboy via funnel.
Once I got it all in the carboy, I realized I hadn't taken a sample for an OG reading and all that was left in the wort pot was some soggy pumpkin and wort slurry, which I tried to get a reading from (having pitched the yeast already, I didn't want to mess with the carboy), and got 1.056, but the recipe indicates it should be 1.076. I'm going to assume it's higher than my reading because that malt had to go SOMEWHERE.
It smelled wonderful, maybe a bit more hoppy than I expected but I like hops and I expect that will mellow with time. I'm told by SWMBO that it's bubbling merrily along and the wort is even swirling in the carboy (no idea why), so I think it's looking good.
I'll post more updates as I have them! Wish me luck in getting a wonderful brew out of this.