Hey, i have a 94 Bird LX 3.8L base model, with drums on the rear axle. I seem to remember seeing 7.5 embossed on my differential cover. I want to change my rear end to a stronger one to accomodate my increasing number of performance mods. I also want rear discs, I want to change my ratio to 3.55 or 3.73 and i want limited slip. Should i replace the whole axle with one from a supercoupe or a V8, or just buy the discs, calipers, hubs and all that, change the gears in my existing axle?