I don't think they would do the car as bonus in Make Your Move, more likely they would tack on a number to the board or make modified numbers that are a little bit smaller to have 10 numbers (assuming 5 digit car, 3 digit prize, and 2 digit prize) in the normal space.
They offered a car in Punch a Bunch during Dream Car Week last season and cars were offered during the all Plinko show in 2013, I wonder if they would make any other cash games the dream car game. They could make the dream car the top prize for getting everything correct on the first try in Time is Money and for getting everything correct in Hot Seat and Pay the Rent. Were 1/2 Off and Grand Game ever played for a car instead of the usual $10,000? I'm pretty sure no for Grand Game, but I have some vague memory of 1/2 Off being played for one at least once either on Dream Car Week or another special.