tone master fender

how do I get a metal sound from my amp?
I have a fender yale reverb amp with a bass, gain, master, reverb, volume, middle, and treble adjustment. I have a les paul custom guitar, if that helps. How will I get a metal tone out of this? From 1 to 10 tell me which adjustment I should have each set to.
i have an amp already with a metal tab.. maybe u can buy a new one? or just like the otha guy said max ur distortion rock on
Fender Tone-Master Custom Shop and Telecaster CS (Clean)