Richie's shirt changes in the episode "Fonzie Vs The She Devils"

In the episode "Fonzie Vs The She Devils", Richie, Potsie and Ralph are wearing ugly loud jackets. Richie hates the jacket, but just as the taking the jackets off, one of the She Devils remarks "sharp jackets", and the She Devils invite the 3 guys to party. Once Richie realizes that he won the prize for "Best Nerd', he tells other guys there, that the She Devils really weren't interested in the guys, and they just wanted to make fun of them. Most of the guys leave, but just as Richie, Potsie and Ralph, are trying to leaving the realize that the "She Devils" have captured Chachi and the plan to shave his head, because he dumped Bertha's(who is the She Devils leader) little sister. So Richie goes back home to inform Fonzie. Fonzie says to stall the She Devils", before while he coming up with a plan". Just before Fonzie arrives posted as "Artie the Nerd", Richie pulls the electric shaver cord out of the socket and stuffs it his White shirt, and coaxes the She Devils to get the cord if he's they've go the guts". Bertha rips Richie white shirt to get the cord. Then after "Artie" rips out the sink, they go back to Arnold's When Richie is removing the chain that connects the sink to Chachi's leg, it is obvious that Richie is wearing a pinkish reddish shirt. Even if Richie had gone home to change shirts, wouldn't have he taken off jacket. But he is still wearing that ugly loud jacket at Arnold's.