In 1996, Hopper joined the World Wrestling Federation (WWF). He was given the gimmick of T.L. Hopper, a wrestling plumber. After a series of vignettes showing Hopper at work, he debuted wearing low hanging jeans and a stained undershirt. He would carry his plunger (named "Betsy") to the ring with him, and celebrate his victories by sticking it in his opponent's face. His biggest win was a "home improvement" match, where he defeated Duke "The Dumpster" Droese.
Although he did not wrestle on any WWF pay-per-views, he made an appearance during the "Bikini Beach Blast-Off" segment on the Free For All show immediately preceding SummerSlam 1996. Based on his experience as a plumber, Hopper was chosen to investigate a brown object resembling feces on the bottom of the swimming pool.
After taking a brief hiatus, he returned to the WWF in September 1997 as Uncle Cletus, coming from the audience to help the heel tag team of The Godwinns (Henry and Phineas Godwinn) in a match against The Headbangers. He hit Mosh in the head with a horseshoe, allowing Phineas to make the pin. He was then billed as the uncle of the Godwinns, and became the team's manager. At Badd Blood: In Your House, The Godwinns won the WWF Tag Team Championship, with Cletus in their corner. On October 13, Cletus interfered in another match, but his interference backfired and allowed the Legion of Doom to win the titles. Following this, the Godwinns attacked Cletus, who was never seen in the WWF again.