Put a picture up I want to see this sr20ve throttle by wire you talk of. To run TBW you might be forced to run AEM S2 EMS.
I assume you have a 20v/primer a p12 with drive by wire??? I'm not sure aem makes a plug and play for that car so you might be looking at aem Infiniti EMS universal. That's big money and lots of wiring. Good luck.