How the #$!% do I disconnect this '95 fuel line?

Heya, working on a 1995 Ford E250 cargo van 4.9L L6 with 176k miles. The
fuel filter looks like it hasn't been replaced since it came off the
production line.. My old '93 Taurus had those easy to remove plastic clips
that secured the fuel line to the filter. The lines on this van are
secured to the fuel filter by these metal nozzles, which I'm assuming are
the 'quick connect' type. While the filter itself is thoroughly rusted,
these connectors on the ends of the fuel lines actually still look decent
with no rust...perhaps they're aluminum? I bought one of those
scissor-style fuel line disconnect tools from carquest with a 3/8" and a
5/16" end. I've been pulling, pushing, yanking on both the filter and the
line, and cussing for an hour here with no luck and I don't want to end up
tearing the line apart just to get this disconnected. The illustration on
the tool packaging indicates I am supposed to clip the tool around the
filter input/output and push it into the nozzle of the fuel line.. and then
the line is supposed to disconnect, right? Laugh at my problems if you like
as I'm still learning things, but as the topic states.. How the #$!% do I
disconnect this?

Thanks,
Jay

By pressing the tool tool all the way in, and give a slight twist on the
tool and line all at the same time....
See, over the years the teeth inside become a little stuborn and it does
become a pain in the ass.