I do need a fuel pressure gauge due to my fuel system. Iam running an intank 255 and and inline bosch 044 so I would like to monitor fuel pressure incase of the failure of a pump. Im also going to be running a base pressure of 100psi with the new Injector Dynamics i bought so I wanna make sure that pressure isnt going to drop or else ill be building another motor. For your TDi i wouldnt put any gauges on the pillar. Get a boost guage and thats it. Mount in ontop of the steering column