TV STUFF: Tiffani Drops Amber

Guest-starring on tonight’s “Two Guys and a Girl”: Tiffani Thiessen, hold the Amber. Yes, the ex-“Beverly Hills, 90210” starlet has jettisoned the Val-gal-sounding middle appendage. The actress is trying out her newly shortened name on “Two Guys,” the ABC Wednesday night sitcom on which she began a six-episode stint last week.

Thiessen‘s publicist, Elizabeth Much, tells that the former Tiffani-Amber opted for the change because “she’s well into her 20s. She’s not a young girl anymore.”

The one known as Tiffani-Amber Thiessen made her TV debut at age 15 on the NBC Saturday morning sitcom “Saved By the Bell.” She moved to “90210” in 1994. And while she exited the Fox soap in 1998, she’s back at work on the series this week, filming its swan-song episode.

And, yes, when she returns to the ZIP code, she’ll return as Tiffani Thiessen.

No word on when (or if) she intends to start spelling her first name with a “y.”

FIRST THE SERIES, THEN THE PROTEST: ABC’s “Wonderland,” the new medical series from ex-“Chicago Hope” doc Peter Berg, is coming under fire from an advocacy group for portraying the mentally ill as “killers, crazies and freaks.” The show is set to debut at 10 p.m. EST/PST on Thursday.

PLAN YOUR VIEWING SCHEDULES ACCORDINGLY: Fox’s semi-hit “That ’70s Show” is set to bow in syndication in fall 2002.

BORING ITEM ABOUT A NETWORK SUIT THAT WE NOTE IN THE SAKE OF COMPLETENESS: ABC President Pat Fili-Krushel announced her resignation Tuesday, effective April 10. She’s leaving to join an online health-info company.