i have seen a cummins in a newer chevy suburban. it looked really good and the guy claimed to get 20+ mpg on the freeway. a lot of off-roaders have made the cummins swap into many different vehicles, they are prized for their tourque and buildability. I wouls imagine that they would be just as valuable in an old truck too, if you spent much tie trailering or working your truck it would be a great swap.
