I've been thinking, which car games, that have debuted since Cover Up would be backwards compatible with four-digit prices? Obviously, fee games would be compatible (Pass the Buck, Rat Race, Let 'em Roll, Gas Money [which would be strange, considering the $10,000 payout, unless you halve or further reduce the maximum payout]). Some games which just print the price on a card or something similar would be compatible (More or Less, That's Too Much).
Stack the Deck would be incompatible as it is, because of the amount of fakes and grocery products used for revealed numbers. Cover Up is incompatible, because of the way the prop is built, and you'd have to have three choices for the first number in a 4-digit car. Line em Up may work, but you'd have to deal with how strange giving away the last number free is.
Pocket ¢hange can work, just eliminate the free number and remove or cover up one of the numbers from the prop (probably the uppermost one).
What do you guys think?