I assume it would connect at the fuel rail, but with a FP gauge and a wet kit won't it get busy over there? Also do I want just a standard EFI switch like this one offered by Nitrous Outlet.
nx-11720 EFI Fuel Pressure Safety Switch Only

 

Or this Edelbrock
350-72214 50 psi Fuel Pressure Safety Switch

 

i went to put mine on yesterday and i didn't have the correct connection to have it come off the rail so i'd like to know as well

 

I ran the the line from the fuel rail to the FPSS to the NOID.

Rail--------------------FPSS-NOID------------------Nozzel

 

Why do you need a FP gauge?