Here's what I learned a long time ago. If you want a car to drive on the street, drive what you have. If you want a car to use on the track, buy a track dedicated car. You can't have both with your NSX. The creature comforts for a street car just don't work well with a track car and vise-versa.
truer words have never been spoken. ask me how I know.
if you insist on modifying your street car for serious track use, safety equipment will gobble up your $10 K budget quickly. Full cage, proper seats and harnesses, electric and fuel cut-offs. I assume you have a nomex suit and HANS?....
the problem is you will end up w/ a car that is worth less than it was before you started and there is a tiny (ie, microscopic) resale market for track-only NSX's.
I spent thousands on my Elise and ended up w/ a car that was virtually unusable on the street and I sold it for less than I could have if I had left it stock.
Anyone that says you can make the money back parting out the mods and returning it to stock is high...
I've got a buddy w/ an E46 M3 that is into it to the tune of $80 K and he hasn't even installed a cage and proper race seats yet, hard to watch...
sorry for the bucket of cold water, but I think you should quit while your ahead and just buy a cheap old race car that you won't mind balling up at the track...
remember, there are two kinds of cars at the race track, those that have crashed and those that will.