Sounds a bit of a dumb question ill admit, but i bought a spare fuel rail for a 2wd saff cosworth (a random ebay moment)
and the plastic fuel feed line had been cut about an inch from the rail,
for the life of me i couldnt see how this pipe pulled away from the fuel rail so
in the end i actually ended up cutting the plastic pipe with a stanley blade.

the plastic pipe did not come away from the rail AT ALL

a bit further down is a round metal (what looks like a one way valve)
with a metal clip on it, when the clip is removed is the whole valve thingy meant to come apart releasing the pipe complete with the union?

if youve ever seen one up close you'll know what i mean, i looked in the manual and it doesnt really say much other than you use special tool number so and so .....