Craig T. Nelson's character on "Coach" was named Hayden Fox, and they never hid that nor played games with it. Bill Faggerbakke's character was usually called Dauber, but his name was given as Michael Dybinski from time to time.
But this is "New Girl"; I doubt that Coach will have a first name or a last name, or that Schmidt will have a last name.
I just hope that if we meet Schmidt's parents they'll call him "son" or something rather than "Schmidt."
The specs for "Gilligan's Island" gave Gilligan's first name as Willy, but it was never once used on the air in the entire run of the show.
On "The Fighting Fitzgeralds" Brian Dennehy's [conveniently widowed] character was never given a first name: "Dad" to his sons, "Papa Fitz" to his daughter-in-law, "Grandpa" to his grandchildren, "Captain" to his firehouse crew, "Fitz" to his friends. But when Holland Taylor did a guest shot as his sister -- specifically, his older sister -- and even she called him "Fitz," that was too much.