Nice car. As Rick said, tire sizes need to change to accent the car a bit more. Looks like a 225/70-15 on front on a 15x7 rim. Since original size was a 15x8 rim, the 7 looks a bit narrow. However, since these types of rims are from long ago, changing to a 15x8 would not be easy. Drop to a
225/60-15 or 235/60-15 on the next set of tires.The 15x10 on back is good, but looks like you may have a 235/70-15 on back. A 10 inch rim screams for a minimum 255/60-15 and maybe a bit wider.
I do like the painted insert of the slots. I thought that kind of personalizes the wheels to the car.
I never did like the silver side louvers either, always thinking they were "unfinished", however, this is a very period touch to the car, as many did just that. They also chromed the wiper grill, sometimes the wiper door (very bad for driving - sun shines in your eyes), and the grills on the rear deck.
Eldon Hall, is that Cookham? South of High Wycombe? There is an interesting ghost story from there.
None of this is like England, where the plate stays with the car.
In effect, the original license plates are equivalent to a metal version of an MOT sticker. Do you have an original MOT for a 30 year old car?
Now many states have discovered people will pay a lot of money for a personalized plate and they often have a couple dozen variety to chose from, usually one for each state university, ones for ecology, environment, special events, and so on. Once you would see a license plate from Nebraska or Ohio or Florida (good grief, Florida has a different one for everyone living there, it seems!), and they were readily identified to that state. Now, there are dozens for each state, and no one knows where they are from until you read it thoroughly to find the state name somewhere on it.
A lot more than you probably wanted, and of course not what you wanted, but odds of the original license plate is like hitting the lottery.