There are many options, but I don't think simply replacing the OEM filter head and using just the CAT filter is the best, and probably is not a good idea. (Opinions vary, of course.)
Personally, I have:
- a Kennedy single pump (I don't run any tuning) as close to the tank as I could,
- over to a Nicktane filter head (there are cheaper options available now but I got mine 13 years ago or so),
- on that filter head, I run a Donaldson P553207 with a water glass bowl on the bottom (I originally ran the CAT 1R-0751, but the Donaldson has better specs and better water separation), and
- run a Racor PFF50216 on the OEM filter head (as others stated, it's the best!).
Two layers of good filtration; two layers of water separation. Running a big filter before the OEM filter greatly increases the likelihood of continuing down the road if you picked up a bad load of diesel. It also extends the life of the filter on OEM mount which is a lot harder to change.
2004.5 Silverado 3500 SRW 4x4, D/A (LLY), Ext. Cab, Long Bed
engineer837 aux rad, TxC CAI, LBZ MP, Scangauge II, Nicktane aux filter head, KD lift pump, 2008 PS pump, 2011 hydroboost, Frederico Swaybars, Rancho 9000XL, Torklift StableLoads, BFG AT/KO2, Lance 835 Camper often in the bed.