Thank you for the reply. I guess I should have better worded my question. I'm aware that I will need to splice into my sensors and that I will need to use tuner software. My question was more for the box itself. Is it a complete unit? Will I need to solder more stuff in to make it work for our 420a application, seeing how it was setup for a SRT. Is this like the Symtech Megasquirt? Also would you guys chance buying a used Megasquirt unit?