I find it's much easier to peel & seed a pumpkin after it's baked. Just wash the outside, and put it on a foil-lined rimmed baking sheet for 1-1 1/2 hours, until it's tender when pierced with a skewer. The shell and stem will then lift right off with your fingers, and the seeds don't need any scraping. Everything comes away cleanly.
Scoop out the flesh and put it in a strainer over a bowl. Cover and set in the fridge overnight to let the excess water drain out.
Make sure you are using pie pumpkins (sometimes called sugar pumpkins), not jack o'lanterns. Pie pumpkins are small and usually rounder than jack o'lantern pumpkins. The shell on the jacks won't get soft enough to pierce - as a matter of fact it gets very hard when baked. Jacks are much more watery & stringy, whereas pie pumpkins are more fleshy and dense. You also get a lot more meat for your dollar with pie pumpkins. Last week I bought 3 at .99 each, but the jack o'lanterns were selling for $7-8.
If you do get jacks, you will have to increase the sugar in your recipe by as much as 25-35%. You'll also have to make sure to puree it really well so your finished product isn't stringy.
Since pumpkins are available for only a short time each year, I buy several. Put them all on one or 2 sheets and bake them while I do other things. The next day, after they have drained, puree the pulp and scoop it into 1 or 2 cup containers and freeze. Freezing actually seems to draw out more of the water, so when you thaw it, just pour it off.
Fresh pumpkin is 'wetter' than canned pumpkin, so you may want to hold back on a bit of the liquid in your recipe.