Sorry for the late reply guys.
Basically the LED's that I used aren't the same as what are the NISMO LED's. You could use them if you wanted. The ones I used are luxeon LED's which are MEGA bright! So I didn't need to use too many LED's. Basically you need to use a bit of circuit board which you shape to suit the reverse light/stop light. Resistors are used in conjunction with the LED's. I think there were 6 LED's used for the stop light and 4 LED's for each reverse light. It only cost less than $100 to do both the reverse and stop lights.
Here are some pics.
I also had the reverse lights painted black inside.