Need Some Amp Help...Please.

[RabidScoobie]

Ok i need some info\help here on my setup.I currently have a Marshall AVT50 Head running through a 1960TV cab and a GT8 Multi FX.

Now currently i run from guitar to GT8 input-gt8 out to amp input and been using the amp modeler on the gt8..since the amps distortion just isnt much at all.
What Im wanting to do now is use my amps preamp(dist/clean) and use the GT8 only for effects but i want more juice in the od channel.In the past ive always had Peavey amps and used its on dist and no OD or dist pedals.I used a Metalzone when it 1st came out but didnt care for it.

What pedal would I need to drive my od channel with more dist?I was kinda looking at the MXR Zakk Wyld OD but i have no idea.Also with running a setup like this Im guessing Im gonna need an external noise suppressor?

The sounds im looking to get range from classic 70's-Van Halen-80's rock-metallica-pantera.