In terms of time spent, you will be better off restoring the Demon, if it is a more solid car to start with. Are you swapping the whole roof, or just the moon roof? The time to swap the moon roof over from the Dart isn't even comparable to the time needed for BOTH quarters. To do them right is easily 15 to 20 hours PER SIDE. And I am sure that you will run into hidden rust problems, you always do on these cars. Plus, you say the Demon is better off to start with, so if having a moon roof is the only issue, why not restore that one? Just my .