Paramount wanted director Dave Thomas to go back and reshoot some scenes before its limited release in 1989, but in the intervening two years star John Travolta had gained over 30 pounds, which prevented any new scenes being shot.
The trivia item below may give away important plot points.
There was another ending filmed. A car chase that ended with a 56 Chevy. Sedan being rolled on the main st. Of Niagara on the Lake, . At the roll over ramp the car hesitated a bit and the right speed was not reached so the car didn't fly through the air and roll correctly. That scene was cut. I was there as it was my car . I waited two years for the movie to come out only to find they cut the car scene