The 1/4' plastic tube-out from my water filter to the inlet valve of my ice maker has deteriorated. It detaches easily via removal of a 1/2" nut from the valve but I am uncertain about the other end, which passes thru a rubberized seal inserted in the back of the refrigerator. Must the seal be pried out or can the tube simply be pulled off? Or is it necessary to remove the filter?

Also, the parts diagrams are unclear as to whether tubing is sold with the 1/2" nut pressed on to one end.

Any help will be much appreciated.