I do remember, they bought B727's with windows in the late 90's. The aircraft were specially fitted for a quick change. As opposed to a CF, I believe the seats rolled in on pallets locking and connecting electrically. They actually operated for several years.
All 727s came with pax windows except the very last batch sold to FedEx. Most freighter conversions have them plugged and painted over. Boeing built QCs, Braniff ran some in the late 1960s and early 70s. Fly pax in the day, in the evening yank the interior out and load up and fly cargo at night. Sunrise found them having the pax interior reinstalled. Having never seen a Seven Two with PDUs I doubt they rolled in and locked electrically.