Whats the Diff??

[Bugs]

Hi All,
I know the standard diff in my MS55 is as weak as shit, and as I am in the thows of doing a 1JZ and R154 swap need something that will hand the standard 280ish hp. The are upgrades that will be done down the track and will want to see about 400-500hp out of this thing. I am starting to watch where my dollars are going and as the engine will be mostly stock (ecu upgrade) I want to get out of this as cheaply as possible whilst still getting something that can down the track handle the power. To keep my Engineer happy and my safe it needs to have disc brakes. Now I am not a drifter or drag racer and the car will not be used for burnouts or the like. It will be just a fast street cruiser. I was initially thinking of getting a BorgWarner out of a Turbo xr6 Falcon ute and getting it cut down but pricing here in Canberra seems pretty high at $2.5-3.5k. I liked the idea of a skyline rb31 diff as the are a 4 pinion 28 spline diff and can supposedly handle 400rwkw (if you believe the skyline guys) they are dirt cheap to buy ~$100 - $300 and come in the right ratios and widths. the downside is they are offset to the passenger side buy 100mm and I after doing some rough measurements I don't think it will fit properly. This then leads me to the BorgWarner out of a ef Falcon (same as rb31 diff but wider) and getting it cut down.

I am also conscious of the unsprung weight that a diff is and am trying to keep this down to improve/maximise handling where possible.

Any thoughts or experiences?

Cheers

Ian.

[Bugs]

Doing some more digging...
Have I got this right?????

Is the yoke offset and therefore the drive shaft is at a sideways angle from the gearbox to the yoke?

Or

Is the yoke centred in relation to the car and the housing (pumpkin for lack of a better term) is then offset to one side that then gives one axle shorter than the other?

If the second scenario is right then happy days!!! I will scrounge up a manual Skyline diff as the ratios are what I am after, it has the disc brakes (just need to do a stud conversion) and down the track I can put an eaton trutrack in it.