i wanna tear fucking concreate

aight im goona cut out my back fenders and replace so it will fit 20s. any other details i should know in this area, i heard sumin about a shorter axle or sumin. BUT next i know im goin to have to cut my fire wall sum cause i wont to lay frame on 19s in front but other than that what could be keeping me from draging the frame. I know my tires are wide but that has to fucking change any way so jus help me out it would be appreciated