Here's the deal with hooking up a nitrous kit on an 03/4 without the Schraeder valve. For some reason it was yet another thing Ford decided to change the year before they kill the SN95 body style. First off,I would not recommend drilling into the fuel rails. It's just not a good idea seeing as how it's not something that can be done without rigging it. NX has designed a special fuel block that taps into fuels system via the sensor housing on the drivers side fuel rail. It will still use the same sensor as that is the new superfantabalous electronic version of the schraeder valve (yet another computer that will now be computer controlled). This is not a mass produced product and will be contructed on a request basis. It's $50 and it's the only safe way to tap into the fuel system. If you have any more questions or need contact information just send me a PM and I'll let you know who to contact.