Wheel Advise
 

I have a v6 2000, and plan on the following mods.

Currently
Intake, headers, and exhaust.

I am going to get Cams, Heads, Manifold Intake, Pistons, Nitrous 175 shot.

Should I get a 17x10.5 rear, and 17x9 in the front.

Or should I get 18x10 rear, and 18x9 in the front?

What are the advantages of each?

First of all you are heading down the wrong path with your modifications. Those mods you listed are way too time consuming, too expensive, and will offer only marginal performance. The 175 shot WILL blow your motor on the first hit with stock pistons and forged ones will cost you AT LEAST 3K in the longrun.....

You need to focus all of your attention on a blower kit. That will be the best way to add power on your V6. A nice procharger kit come with a front mounted intercooler and it costs about $3400. That supercharger alone will give you enough power to keep up with a modified mustang GT or maybe an LS1! If you have the money then I would really just buy a GT or a 98 Cobra....
All those mods you listed I guarantee will cost at least 5k.

Your digging youself into a large hole if you dont just go with a supercharger. On the 4.6 you can get away with just a nitrous kit but you need boost if you want a V6 to run.

The wheels depend on your personal preference. The 17's will be better for performance. The 18s are more for looks while still giving some good performance. The 18's are taller and heavier.

V6 Challenge.
 

I seen a few v6 mustangs running 10.4 runs.

The SuperSixMotorsports has this parts with out blowing the engine.

I am thinking of adding the ProCharger instead of the Nitrous, with all the parts. What I am worried is that if I place a Procharger with more than 8 psi I will blow my v6 engine also. Right now with those parts with out pro Charger, injectors, and Xcal II I might be around 250 rwhp.

Yes the parts with pro charger will cost around 7k, but the face of the guy with the GT will be priceless.

if your serious about doin engine work to your 6 banger I'd talk to some of the guyz on 3.8 they have ALOTA guyz running Super Six Set-ups with blowers and nitruous...