G'Day Brad,
The structure is the same but some of the included parts are different depending on the model,
The diff ratios will be different between auto and manual and grades, SS Manual is 3.45:1 diff ratio, and autos are 3.2:1, omega is 3.2:1 and 2.92 for auto. HSV have 3.7:1 for manuals, SS and HSV are all LSD, everything else is optional,
Also, half shafts and CV's changed for the bigger at some time, Ian's half shafts suit the old 2006/7 models, but he is in the process of making up bigger diameters to suit the latest, i know....., i'm waiting for them now.
You need the CV joints from the existing half shafts included in the cradle assembly.
Also brakes are different, depending on the model, rears range from 302 to 324 on Holden range and bigger on the HSV's, but these wont fit on 17" rims or less.
The Tie Rod Arm also changed at some stage to a fixed length pressing, previously adjustable, see pic below, Holden don't sell the old part, only the replacement.
If you haven't bought your kit yet, don't be in a rush to get something that may not meet your needs, Skulk ebay, tradingpost, google, and some VE wreckers etc until the spec you want comes up or is being parted out of a suitable wreck, i wanted 3.7:1 lsd diff so watched for a month or so for a HSV car to pop up, mine came down from Dubbo, see below,
So make a list of what you want, find the appropriate model, and wait for it to come up,
hope this helps.
Try and get the handbrake cables as well, the wacker that removed mine cut them at the hubs to save time, they cost a fortune from GM.
Complete cradle less brakes and springs/shocks....ideal
Diff Ratio and details on Label
Required Arms and Knuckle, see adjustable Tie Rod on Right Hand Side
cheers