We see a ton of Chevy engines around here and a fair amount of Fords, but for whatever reason not enough Mopar mills. Seems that unless it's something nuts like a Hemi or multi-carbureted wedge, then ...
Some people just want their vehicles to be a little different than the norm. It may be for looks, or it may be that people simply want to go faster. There are others who want the truck to look cool ...