Then i would say you know already everything to solve your problem.
- you have the ID of the current selected item (that’s the main-problem here)
But with mine code you have already the current-ID of the selected item.
Now you can work an do what ever you want with it.
I see no other difficult problems.
You are not able to open a light-box?
You are not able to send the right data to your light-box?
You do not know how to save it back to database, because you do not know in which row you have to save your data, when clicking the SAVE-Button?
But wait! You know which is the selected row 
(you got this informations already).
-
you know the current ID
-
you know the current index (by doing a query of your data and searching for ID)
What do you need to know more???