This is what the placed tee nut should look like from the top, you’ll be covering this with padding and felt later so it doesn’t have to be real pretty yet.
You cant really tell from this view but the center hole is drilled all the way through, and the countersink hole is just enough to fit the t-nut in place.
The bold will come up from the bottom and go into the tee nut – but now far enough to go all the way though – it would make lumps on your table.
I used a total of 5. (four corners and one in the middle)