Throughout the course of the first season of Knight Rider, the show didn't have a dedicated "blind drive" car (meaning, a dedicated car that was only used for when K.I.T.T. was seen driving by himself). Rather, the crew would simply place the blind drive seat in whatever car was available at that time.
Beginning in the second season, the show acquired a number of additional cars. One of those cars, a 1983 Trans Am, became the full-time, dedicated "blind drive car".
The car was first used in the very first episode FILMED for the second season, "Return to Cadiz". It's fairly easy to spot, as besides the slightly mis-shapened driver's side seat, it also had a rear view mirror mount and a passenger side sun visor still in place. #1967 also (briefly) had the season 1 style overhead console, the only other car besides the season 1 hero car to have it. This overhead can only be seen in #1967 in this episode and the next one filmed, "Ring of Fire", before it is replaced with the more form fitting season 2/3/4 style overhead console.
#1967 makes its debut in "Return to Cadiz"
For the second season, the interior of #1967 was mocked up and not meant to be seen on camera. It featured a telescopic round stunt steering wheel, a custom, long-reach shifter and a half-dash shell that was meant to resemble the overall shape of K.I.T.T.'s dash from afar.
In this screencap from "Diamonds Aren't a Girl's Best Friend", viewers get a quick glimpse of #1967's interior, sans the driver's side blind drive seat.
By the start of season 3, #1967's interior was upgraded. Since the show upgraded K.I.T.T.'s dashboard, they had no need for the season 1/2 hero dash. They removed that hero dash and placed it in #1967. If you ever spotted K.I.T.T.'s 2-TV dash in the 3rd and 4th seasons of the show, that's #1967!
By the final season, #1967 was mostly unchanged from the previous year, except it received the new, season 4 style rubber front nose.
#1967 in a screencap from "Deadly Knightshade"
So, what happened to #1967? As was the fate of most of the Knight Rider cars, it was crushed at the conclusion of the series.