Deano I have an L98 in my Cobra with p/steering but no aircon. I have all the Holden part numbers and a diagram if you're interested, just send me your email address.
The aircon runs on a second belt so leave that out of the equation.
For the other parts just find a VZ/VE wreck and grab the alternator bracket and the p/steering bracket even if you're not running the pump. It'll make it easier to fit an idler pulley in place of the pump. By the way the Commodore power steering works a treat with a VK C'dore rack in my Cobra.
Just beware of HSV models which have the LS3 - roughly 30mm different offset so you need all brackets & accessories from the LS3 if you go down that path. You can tell by comparing the depth of the "spokes" on the balancers.
You'll also need the factory tensioner. I'd buy it new from Holden to make sure it's a good one.
Here's the best photo I could find of my setup. Bit hard to see.
