The Nailbomb is in my cr@ppo Peavey Strat copy, it's a Raptor, one of the older (smaller) ones. It was played straight into the Toneport and recorded with Cool Edit. No post-processing at all. I don't know how ;).
Do you not like the Ubermetal WFD? I had one once and I thought it sounded brilliant. My mate has a Metalzone and it's fizzy and boomy in comparison (IMO). In fact the best metal tone I've ever heard was an Ubermetal plugged into an Engl valve amp.