ok heres what i got going on, i have a 87 suburban, i bought it as a running project and thats exactly what i got, its lifted 4 inches, on 33 inch tires, and it drives like ****, runs well but drives horrible. it takes me a while to get up to 45 50 miles an hour. and wont go over 55 or so. im figuring i need a diff gear swap probably to 4:56? my question is how hard would this be to do myself? i know someone selling a gm 14 bolt 456 gears, how hard would it be for me to put this in my rear diff. i disconnected my front drive shaft because the guy who put on the lift didnt do anything to the shaft or trans so it doesnt reach. the front lift is horrible, 4 inch block (illegal) and theres only 2 leafs per side. the shock hoops cracked and broke off due to this **** lift. rear lift is fine. so anyone on here know how to swao gears maybe help me out with a step by step?