At the beginning of this story, when Jim and Rocky arrive in Hawaii on a trip they think is a prize that Jim won in a drawing of some kind, which turns out to be a scam. Rocky says that he has never been in Hawaii before. However, Rocky had visited Hawaii in a third season episode, Dirty Money, Black Light (#3.22), where Rocky also won a trip to Hawaii (but he went alone), which also turned out to be a scam, although a different kind of scam.
When Jim and Dwight (the rookie government agent) arrive at the hotel, they are driving a rented Mercury Monarch. As they get out of the car Dwight asks Jim to put the briefcase in the trunk. As Jim does so the trunk clearly shows "Plymouth" with the lettering centered over the trunk lock. Later, the Mercury is shown again from the rear and the model name "Monarch" appears only on the passenger side of the trunk not centered over the trunk lock.