What this needs is the full manual content. Braniff flew DC8s on longer runs snd their 1st class had raiseable armrests. Is this manual for the 727 or the DC8. As far as the fuselage resembling a 707, the 707 was larger had 4 wing mounted engines. The 727 had three engines, one integral with the tail assembly and two mounted on the rear of the fuselage under the tail. The 727 was a narrow body aircraft unlike the 707. Also in 1979 I believe passengers still boarded in most airports from the tarmac via stairs not from terminal connected tubes, so Ms. Leeds would have seen the aircraft she was boarding.
This whole conversation feel like a scene from “My Cousin Vinny”
I agree with everything except your statement that the 707 was unlike the 727 in that the latter was a narrow-body aircraft. The 707 had a single-aisle configuration with three seats on either sided of the aisle. So it would not be considered a wide-body like then747 or the L-1011. Interestingly, as I recall, the 727 could be entered or exited from drop-down stairs in the tail.