Logitech M180 opens the same way.

I too used M3 nylon screws and nylon nuts for the winged pins I broke during reassembly

I only got 30mm and cut it to about 20mm.

On the second A1176 where I removed the heat sink I didn't bother to remount the pins and used 4 nylon screws.

A special note: The second A1176 was much louder and got hot (fan running full speed) easily. When I removed the heat sink I found a die sized piece of plastic between the die and the thermal paste. Someone forgot to remove it when the Mini was assembled originally.