Does anybody have a suggestions as to
what could make this task somewhat easier?
Thanks in advance for any help.

Tony
If the O-ring has dried out enough that it allows the plastic of the
container to come in contact with the housing, it will be darn near
impossible to break it loose. My Son In Law dropped the O-ring and didn't
notice and put his back together without. Had a rough time getting it back
off to put the O-ring back in. Also, is it possible that calcium has built
up over time on the threads, making everything a tighter fit. A good soak
in Vinegar might help if so.

Tom G.