The cooling lines are attached ( in a fasion) to the outer sides of the liner, they tend to come loose after a while & will
Snag on both the insulation and the outer shell as you attempt to pull the tank ( liner) free.
It may help to slid some pieces of cardboard down between the sides of the liner and the outer shell as you pull it out, also, a second pair of hands helps too.
The cooling lines are attached to the compressor so you'll need to un bolt the deck and prepared to lift everything out unless you are experienced in refrigeration and can remove the cooling lines properly by evacuating the freon, etc.