I recently ordered the Glacier MK-2 fuel filter kit. The question I have is the kit came w/ the fleetguard FF5320 filter. I remember reading in a post before to switch that filter for a Donaldson P 551313 or a CAT IR-0750, I cannot remember which filter would be better to have in this location. I will be installing this kit on all four of my third generation trucks and would like to order a case of the right filter, Thanks - Frank.