Aloha
I forgot to mention that I prefer to use allen head machine screws as replacements screws. Easier to use, can actually use a torque wrench on them with an allen driver socket for consistant tightening torque on all the screws.
The screw is easier to remove and less likely to have problems with buggered heads and screw drivers missing or slipping causing damage. The head size is usually smaller and more likely to fit the small recess hole. Works wonderful when using higher rated screws also.
I actually use Allen head screws for all my speaker mounting when I mount my speakers. Some times I need a washer under the heads. Less likely to damage the surrounds and cones too.
Steve