make sure to use glycerin filled guage or a snubber fitting as my fuel guage went all whacky from surge/spikes in pressure , ill get it right eventually ,the filter w black drain is the one to crack open to prime ,and swap the inner thick washer style gasket from fws 3003 filter to filter fs 1001 as per fass instructions as the don't use a inner o-ring any more throw it away , I also used the second back bed bolt not the front one , fass is updating the instruction sheet, this was a 2005 lly, filters are up high and don't hang down,also cat , Baldwin Donaldson ,and some others filters cross reference w 1-14 threaded nipples , can see the list on fass ride.com,,be ready for some fuel to squirt out w towels , and catch pans etc,when initially priming, was told by fass I should see 8-10 psi , with this set up, I did have to remove the return nipple and stretch the spring a quarter inch ,as the pressure was only 5 at first