I would beg to differ, I own a 98 RS, and have a Hahn stage II. While agree it might be easier to sell your NT and buy a GST or GSX, The 420a is a well designed platform; more than a decade newer than the 4g63. Don't get me wrong, the 4g platform is a great one, capable of producing 400+ hp on stock internals; sometimes you must work with what you have. (Hence why I own a converted NT) If you are looking for some more info I would be happy to share what I had to do to mine. In the meantime might I suggest:

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