I really need to do something on both the Coronet and the Imperial. The Imp would be fairly easy, with the split front seat; but the Coronet and its console would be far more difficult. I had thought about taking an extra console glovebox lid and drilling one hole in the top, the same size as a cup base, then installing a plastic cup holder in that spot. Of course, that reduces the capacity of the console storage by at least a third, if not more. And cutting a hole like that in a console lid would be tough, considering the material that lid is made from.
The D300 is not a friendly truck to drive, while doing anything but driving the truck! Manual steering and a four-speed kinda require more attention to the road than my Passat does! Still might put something on the floor hump, like the roll of duct tape in a previous post here, and a wee more permanent.