BigNasty,
Most of our trucks are specced with the Davco's in various flow rates depending on the size of engine. I have seen then on medium dutys with a 5. 9 Cummins.
I will try to get you a link later today or tomorrow.
They should be mounted where you can easily see them as the fuel level in the clear top dome indicates when the filter element needs to be changed.
We have had very, very good luck with them and one feature that we really like is in the event of a failure (cracked cover or similar catastrophic event)on the road you can remove the dome and element, then there is a threaded stud on the base that accepts a Detroit Diesel or similar spin-on to get back home.