would i need to modify anything? like brake lines, driveshaft, or lower the transfercase? and can i just make new shackles out of the same thickness or thicker metal? and would that coupled with a 1 or 2 inch body lift nessesitate any other mods right away? also, my ckeck engine light was on for my O2 senser not being hooked up. the other day i found a little box on the floor of my jeep on the drivers side, its about an inch to an inch and a quarter in length, about a half an inch wide and about a half an inch deep. (pic below) the wire or wires were corroded and had broken off. now i have no CEL on but the senser is still not hooked up. also when i turn the acc on the light doesnt flash. is that related? also whats that box called?