Is there anyone to install one on a s4 NA? I know on my old mustang it fit right on the fuel rail which made it easy. I just want an underhood gauge I can check nothing fancy. If anyone has this set up and has some pictures that would be great

 

You would just need to tee one into the feed line from the fuel pump.

 

5/16 " barb to barb..3/8 npt Fitting inbetween or on the T.
Russell makes them.