Thanks, Akemi, that's really useful, and I'd never heard of it. I suppose that as it gets updated, it'll tell me the most current legacy to use (in my case, the 310.40 worked, but the 340.58 did not... and that was trial and error.
It's all in the README that comes with the driver ... once upon a time, I wrote a script to extract driver info for the installed card (not on CentOS), but nvidia-detect is arguably better.