DropTopSc

hey guys.maybe someone can help me out here.i have a sc430 and i am getting my 20x10.5 +29 offset redone to 20x12.i dont know if this going to work.i dont know what offset to choose but i want max lips.i will not be puttin bbk or anything if that helps .is this even doable ? can someone tell me how they pull fenders because i know how they roll them..and the big question is what is it going to taketo get these sitting right on my car.thanks for helping me out guys..