Reply to Serato & Traktor X1 Midimapping

i recently switched from traktor to serato, i have trade my traktor setup (vci 100, audio2dj, pioneerhdj1000) for cdj 800 and sl1 box and i got left traktor x1...
i already mapped X1 as my other Deck 1, with play rewind pitch + -, but i can't find where to map the pitch fader
any help or solution
thanks