I don't recall this rule, but apparently on Wink's Tic Tac Dough, in the bonus game, for a very brief time, you had to get EXACTLY $1,000 to win the game. I don't ever recall seeing an episode with that rule, and haven't been able to find any video of that either.
Price is Right Bullseye I, Bob gave a range for the price of the car, but on the first or first couple of playings, no range was given to the contestant.
When Hi Lo began, the player selected any item, and then I think the price was shown, and they had to select to place it in the HI or the LO row. Once either the HI or LO row was filled, the other products' prices were revealed, and if they all "fit" in the proper row, the player won. This was scrapped very soon to the current rule of "Pick out the 3 highest priced products".
Again I've never seen this, or recall having seen it, but the earliest playings of Cliff Hangers involved 4 small prizes instead of 3.
Dice Game car prices when it first debuted could have 7s, 8s, 9s and 0s in the price of the car. That changed pretty fast I think...
Make Your Move temporarily had two 3-digit prizes and one of the digits "overlapped" in the array, but that got too confusing so they changed it back to the 2, 3 and 4 digit prize thing again.
Pass the Buck, the first few playings had 8 numbers instead of 6 on the board, and all 3 picks had to be earned by passing the buck. That changed soon to the 6 numbers and 2 pricing of grocery items + 1 free pick given rule.
During the first playing, or maybe the first few, of Pocket Change, all 5 numbers had to be filled in by the contestant, the first one hadn't been given for free.