You can fix all the little broken tabs with super glue. You have to really take your time though, and make sure you're gluing each piece in it's original place, you will have to look very closely at how it broke to make sure it fits perfectly together before gluing. Also wait at least an hour for the super glue to dry or it will be weak and get white residue all over the motherboard from evaporating.

Also refer to the service manual to help you, it explains exactly what to do. Most importantly, TAKE YOUR TIME and be patient. I think this could have all been prevented if you just took a deep breath and thought about it before digging in.

Put everything back together first and try again before buying any new parts. The processor may have overheated but it's possible that it will still work.