In Kansas, you can put an old tag on an antique (25 years or older). It has to be the same year as the car. For example, about 15 years ago I found a 1969 Kansas tag at a swap meet. I bought it and it is now on my 69 Barracuda. you can see it in the picture below.
View attachment 1716190524
I paid a small fee for this favor, and not a penny since. Every year it costs me $25 to keep the car's registration current.