I have a Kustom 12 gauge combo amp, a digitech rp 255 effects pedal, and an epiphone les Paul. I'm trying to get a hard rock tone, like slash's tone. I know I don't have a Marshall, and don't tell me to buy one because I'm 16 and broke. Anyway, effects pedals are confusing. On mine, it has an amp option, and a distortion option. I chose a Marshall jcm800 and an ibanez tube screamer. How do I adjust the gain/tone/filter? It ranges from 0 to 100 on each option. Any help I will take, and please answer because this is making me mad