When I was a kid, Dad had a FC-170. A year or two ago Jeep was going to bring them back as a concept vehicle. I don't know if they ever put them into production. Haven't seen one on the road. Old Jeep trucks, to include the FCs were rust buckets. Ran well and could go places off road, rust buckets though.
Have a friend that bought an M715 a couple of years ago, redoing the whole thing, except metal top instead of canvas, and he put an Olds diesel in it. Don't know why he picked an Olds diesel, but its his and he did.