I used the NOS 5171 kit for a '96 GT AODE. The car bone stock ran 15.3's. After bolting on the nitrous the car immediately ran consistant 13.8's. The only people I know that still make cams for the modulars are Sean Hyland. And at a price of $900 and up I would wait on them until you have all the bolt ons you plan on getting and then get the cam suited to your combination. The problem you may have with your '99 is the returnless fuel system. You may have to check with NOS to see if the kit will still work with your application.
Cobra9450
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http://www.geocities.com/MotorCity/Show/9763/
'94 Cobra - Bullet MAF, 70mm TB, pulleys, MAC headers, h-pipe, Borla catback, E-303, NOS 5115- 11.93 @ 114.17