Dual Filter Setup
 

Hi, I'm new here so I thought I might as well start with the stupid questions. My "new" cummins has some napa filter connected to the regular filter mount on the block. This filter does not have any attachment for a fuel/water separator drain or sensor. Is the drain necessary or can I just get a fleetgaurd filter without the drain (FS1251).
Secondly, my truck has another filter mounted on the frame on the driver's side. This also has a NAPA filter, it looks like this:

https://www.dieselbombers.com/attach...1&d=1342647591

I checked the part # with NAPA, and the filter belongs on a heavy duty detroit diesel, 11 liters and bigger :s: I've checked to see if it was an FASS or air dog or something but those mounts look different, mine looks like this:

https://www.dieselbombers.com/attach...1&d=1342647591

Can I just use the same fleetgaurd filter or do you think I need a special one, or do I need to abandon the the second filter.
Thanks