Hi Roger,
Based off of the Everymac pages for the [https://everymac.com/systems/apple/imac/specs/imac-core-2-duo-2.4-20-inch-aluminum-specs.html|2007] and [https://everymac.com/systems/apple/imac/specs/imac-core-2-duo-2.66-20-inch-aluminum-early-2009-specs.html|2009] 20” iMacs, I’d say it just might be feasible. If you’re willing to open the 2007, you could compare the connection cables as seen in Step 8 of the 2009 20” iMac teardown. If they look similar, it might be worth a shot.
Though before you open anything, take a peek at [https://www.ifixit.com/Store/Mac/iMac-Intel-20%22|this page] to see if you can find anything that might help in your case. If you know the EMCs then it’ll help you determine compatibility of screens like [product|IF168-000|this one].
Hope this helps!