Put some penetrating oil on those lines.
there are little O-rings that seal against the tube.
Wiggle them and twist them, if possible, to get them loose.
When reinstalling, I put a small amount of oil or even light grease on the tube end to help it slide in.
I bet it's slightly crooked and applying pressure.
bolt on the side of the block near the front holds it...
Unbolt/loosen it and you might get some more wiggle room.
And I removed and reinstalled my engine oil cooler lines with the front axle out of there.
I haven't tried with the front axle in.