72RATCAMARO

so i recently acquired a sonoma with a ls6 t56 swap and it still has the stock rear end with 4.11 gears. i need a stronger rear end to handle the power and hook and book. it hooks incredable right now and i dont know why it is a one tire fire most of the time and yet it squats and goes. but i am gonna break it first time on slicks i can tell ya. so i need to go bigger and stronger. i was thinking doing a 4 link but its my daily driver. i want to mini tub it and run a 335 rear tire. so i just am looking for input on how to set it up. also i have a firebird shifter which is very notchy but i am looking for just alitle better. with the bench seats and it being a truck anyone know which short shifter would work best without making me have to gangster lean to shift. also i cant get the 5 speed ball off the firebird shifter. the whole stick comes up. any ideas? thanks in advance