Sorry, I ate a bad taco and totally paying for it.....
You should be 100% fine.
Kind of a rudimentary explanation for how drivers work but....
You install a Driver > driver gets stored into Windows System Folder
You insert a New Card > Windows looks through to see if it can locate a driver
If it can, it will either use it automatically, Ask you first and you will get a prompt, OR you have to tell windows in device manage to update the driver.
Driver folder will always store the drivers until they are either replaced or deleted!
Soo unless your 1080 driver "replaces" the 970 driver, the most you would have to do is run nvidia experience again/device manager.
side note: chipotle is doing a teachers/educators get a bogo.