As much of a stickler for rules as he is, coupled with his pride in the US Postal Service, Cliff would well be aware that it is a Federal crime for anyone other than a letter carrier to handle undelivered mail. This is one of the first things letter carriers are taught and Cliff would know this, no matter how sick he was.
Cliff: Norm will be okay.
Carla: Hey you know, Norm isn't at some party you know. I mean by now he's probably had all his valuables taken, been strip searched, been deloused, and thrown into some dark cold cell with a sex starved pervert.
Cliff: So? That's how he describes a typical evening at home.
Cliff: As long as I'm carrying this bag there's one thing that will never touch these lips.
Carla: You mean there's something that wants to.
Coach: What would you say to a beer, Normy?
Norm: Daddy wuvs you.
[Norm offers to deliver the rest of the mail on Cliff's route]
Cliff: Ah, Norm, you're not trained. You're not qualified.
Norm: What qualified? You drop 'em in a slot. A chimp could do it.
Cliff: You kiddin', no way. They did a study at the University of Michigan – chimps were 32% slower. Oh, yeah, yeah, yeah, they were better with customer relations and everything...
In episode Woody For Hire, and Norman of the Apes, Norm would literally get a chimpanzee to deliver the mail (as revenge for a similar prank by Cliff.)
Though not his final episode to air, this marks Colasanto's last filmed appearance.