My p600B elbow has the hole right before it hits the intake for the sensor, the hole is round, and the sensor plug is rectangular. It isnt the bigger one it is def in the right place? Help?

 

I think you are talking about the AIT(air intake temp) sensor. I know in my vortech metal elbow I used an adaptor(reducer) to put th stock fiiting in it and then that square sensor you are talking about, in that. The adaptor(reducer) is just a bung with threads on the I.D. and O.D. for different sizes. Hope this helps.....John

 

There should have been a plastic adaptor that you screw into the intake tube to allow the AIT sensor to fit in. If I remember correctly, you have to modify the stock sensor slightly to get it to work.