Piece of Cake ......................
...................... as I replaced mine last year. The end which attaches to the mixing elbow was getting a little ratty from being removed each year for an inspection of the elbow so it was time to replace the 4 foot section. At that time, I payed around $12.00 / foot.
The only tool you really need for this job is your wife's extra high powered hair dryer. Once the connecting joints are good and hot, they come apart quite easily. Mine were 13 years old when removed and came apart easily in spite of the tightly double clamped gear clamps on the muffler end.
Just make sure the wife is no where around when you use her hair dryer or the job can very quickly escalate from casual to high hazard

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