replacing fuel line/return line question

1971 Charger.
I bought the one piece, pre-bent fuel line and return line.

Does the old one just twist out like removing a cork screw from a cork and the new one go in as smooth as a putting a dip stick in the dip stick tube?

Any info on this operation will be of great assistance prior to starting!!!

Also, do you take them out from the front or the rear?

In advance, THANK YOU!

having a hard time understanding.
Twist out from where?

When replacing the fuel line and vapor line in my Charger - the ones that run from the engine bay to the fuel tank - is this a big project or is it pretty simple? I'm just not sure if there's many issues going THROUGH the frame or around and under the frame etc. And with the pre-bent ones, does it make it easier or harder with trying to "FISH" it through everything from front to rear?

Once you get all the mounting screws out it is very easy. It only goes thru the frame in one place I beleive right by the torsion bar cross member.I would order prebent stuff. This is a 71 challenger before I added the third return line: