How to id this engine?

Sep 6, 2021
I was given an old JD L120 lawn tractor.
It hasn't ran for at least 6 yes and the lady was going to trash it. So I accepted it.
It has zero markings labels anything to Id engine. I know it's a vtwin 20hp brigs.
I don't know if it's the cv40 or intek.
How do I Identify which engine it has.
If you figure out the year of the tractor you should be able to make an educated guess as to which one it was. Can you compare side by side images of each engine and pick yours out?
There will be a serial number somewhere even if the regular tag is gone. John Deere is typically good about keeping engine changes tied to unit serial numbers in their parts breakdowns.
I found 406777 after a lot of cleaning.
I don't think it's intek engine. But still not sure