Welcome to the site!! Like said above, theres a member building a 6.0L to put into a ranger. There's guys, not here though(yet), that have put Cummins 4BT's into rangers...infact there was one on ebay a little while back.
One piece of advice.......top right of the screen, there this really neat feature called "the search button". If there's any question that pops up in your head, or you want to see what others did, use that button. The search button is your friend.