Yea good idea my 2c are as follows if it was my car this is what I would do "if wanting to bulletproof the car as best I could" in reality it can be done with a lot less $$$ and some do it with more $$$ but for me this is a real solid build list:
*4 inch dump & high flow cat
*fuel system
*intercooler- don't cheap out here get a good one
*turbo side intake
*Valve springs- you may not need em at mid 3s but they'll eventually go soft anyway
* upgrade standard brakes with better pads and rotors if on budget, if happy to spend put a set of FPV brembos on the car makes a big difference (standard turbo brakes suck)
(brembos won't fit most factory Ford wheels)
* good suspension-- shockworks coilovers
* Oil pump gears
* external oil cooler for ZF or the PWR unit to prevent ZF milkshake
* true trac diff
* IMS diff hat
* Tail shaft- so I can launch it and not worry
* make sure rear end is up to scratch with new bushes and everything all tidy so it drives nicely ( a worn out rear end on these cars makes them feel like a bomb)
* good set of tyres
* service it often
* seeing as though your in Bankstown go see Joe at CMS for your tune he's only at Prestons or go to Spiro at Autotech in Granville both are very good tuners. In my experience Joes prices are a fair bit better.
On factory turbo youl do around 310-320rwkw on 98 and somewhere around 340-350rwkw on e85 depending on dyno who tunes it etc-- at this power level factory turbo is a good option spools nicely and you save money not having to purchase a new turbo ( genuine garrets are so much more expensive now it's a joke)
Factory ZF mite be ok at that power level for a long long time but may eventually need a rebuild keep it in mind, people have broken input shafts with that power but then again some people have been totally fine. Building a strengthened ZF cost is 7-10k depending on spec who does it etc,, just something to keep in mind....
Now you can make that power for a lot cheaper then I've listed but if you went for the list I typed up your car would be a real nice street car and will feel awesome..
The other boys/girls will have a different opinion but this is my personal opinion....
Is your motor really high Kays? Or relatively low?