Let me help you out a little....I have 522 RWHP (on my track tune) with my 4.6 orig 2v block. Your looking at probably 20k+ to get to your goal but atleast it will last and be nice. The cheapest way would be to go Snoball`s way and buy a 03-05 cobra and change pulleys, filter,tune,exhaust and your just about there. Goto livernois motorsports and buy one of their forged shortblocks. Get some svo heads and an svo minifold(outflows the bullitt one) like i have. Cobra forged crank, tko tranny, lakewood BH,fms DS, 31 spline moser axles, FMS trac loc, get youself a blower, I have a vortech v-1 s-trm which is loud and nasty, get the livernois stage 1 billet cams like what i run and your there. Get a good tune and you can ride. I went with the CMR software but make sure you check locally first. The place where i just moved to no one runs any type of diablo stuff so iam prob going to switch too SCT sometime in the future. Since you want 500+ RWHP, then i would go with UPR UCA`s and LCA`s in my opinion best bang and quality for the buck. Shocks and struts are your preferance. If your doing just track stuff go with lakewood, if your doing both go with Koni or tokiko. I still have the stock fuel lines and rails but you will need to get a 255 intanks and some type of inline. My blower came with the 55 gph t-rex along with my walbro iam good.You will need 42lb injectors atleast, maybe 55lbers. Your electrical can stay stock but i would suggest getting a 3g alternator, wires and some NGK or denso plugs. If your going to have more than 10 psi go with 2 heat range colder plugs. get yourself the lightning maf or get what i got, a pro-m blow through MAF. I reccomend the procharger intercooler, its what i run and fits nice in my 96. You will need some gauges, fuel pressure and boost/vacum is a must. I would get a wideband also. I have a PLX one which works great and i reccomend it. Clutch, i have a king cobra which works great but is kind of slow when i try to power shift. UPR blue thunder shifter is what i have and have had no probs with it. Oh,before i forget, the fuel setup i mentioned will def have to be upgraded if youwant to runn close to 600 RWHP. My lines and rail become useless after 6500k on the dyno.
Thats what iam pretty much running and just wanted to throw it at ya. Go with what works for you and your car, but wanted to throw what i have at ya because its been working for me for a while and dont need to change or replace things very often.