There are a number of modules you could use and I'm sure many here would recomend the Blackface as I see it gets a lot of action out there. I'm thinking, SG ... P-90's, sounds like a good time to plug in a JTM. That module is based on the Marshall JTM-45 and it has a substantial low end and is very cutting in the highs. I'd start there and/or Black Face. Depends on how much distortion you want on tap. Black Face = pretty clean, JTM = grindy but still fairly clean. If you want more overdrive maybe a Plexi?
