If you go by the catalog at McMaster, the flat head M3 screws that they carry are 90 degree head angle.
A standard countersink works if you go slow. Use a drill press if possible. Standard HSS bits work for drilling.
*** The Gate - Celebrating 7 years at the same location ***
The difference between genius and stupidity is that genius has its limits. - Albert Einstein
Understeer is when you hit the wall with the front of the car and oversteer is when you hit the wall with the rear of the car