The last D90s were in '97 and none of them were diesels. They had the same emissions-certified engine as the Range Rover. The issue with the D110 and D90 wasn't the emissions, it was DOT air bag requirements, crash tests, lighting and many other standards the Defender series had no hope of meeting. They had waivers for a while and could import very low numbers and escape some of the rules but eventually, it was a no-go. They were awesome rigs and one of the best outta-the-box trail machines that ever wheeled, especially considering LR scoffed at traction aids in that era. LR had some quirky ideas about certain things, some really good and some really offbeat and wrong-headed. Still, they were awesome. How do I know? I worked for Land Rover North America back in those days.