Old D-cell modifications?

Hi All! -
I have just been getting back into flashlights recently, after a long time away from them. Wow, was I blown away by the technology advances. To give you an idea as to how long it has been, up until recently, I was still using my 1980's vintage B-lights (Bianchi). At that time, they were the best you could buy. Anyway, my question is this - Is there an easy way to put a modern LED in one of these big D cell lights, or are they just relics of the past? I have always admired the beautiful machining and the finish on these lights. I hate to see them just sitting on the shelf. Also, I have not noticed any high performance D-cell LED lights. Are D-cells a thing of the past as well?
Thanks
Dave

If that light has a PR flange bulb in it then the easiest mod would be to buy an LED PR flange drop-in bulb. There are a few out there but they're not terribly bright compared to more modern LED flashlights. The best way to go would be to have a custom LED conversion made for it but the cost could be something that will prevent you from doing it.

There are a few D cell LED flashlights out there but they seem to be losing ground to newer Li-Ion and Lithium flashlights. Smaller, lighter flashlights that put out more light appeal to folks more than lights that have really long run times.