IIRC, Vnicepeeps posted about this a while ago. I think puree from fresh pumpkin is more liquidy than canned, so I think she let hers drain some. I'll see if I can find her post about it.
But yes, that is what I'd do, cut the top, scoop out the inside, cut it up in large chunks, and roast.
I like my pumpkin bread with a fair bit of spice and raisins.