It should not matter the order that you put these server behaviors on the page. Once you have added the DataAssist Repeat Selection the names of the form elements will change to be based on the counter.
This is what makes this the repeated form on the page. Both the Update and Delete server behaviors rely on this repeated entry to work. You should be able to apply the multiple update and delete server behavior on this page without issue. In the multiple delete you just specify which field the id comes from, a checkbox in my case. Then in the update you just specify what elements are bound to what columns by using the dropdown options of the value select list next to the lightning bolt.
I'm including some screen shots of what the interfaces should look like so you can compare with what you have in yours.