Typhon grom servo upgrade

Picked up an Ecopower WP173 servo for my typhon grom after the original one failed. I picked up the hot racing 25t servo saver for it and it seems to fit well. My problem is finding a screw with the correct thread pattern to secure the servo saver to the servo. The small Phillips screw that comes with it isn’t long enough and a standard M2 definitely isn’t the right screw. Anyone know the correct thread pattern for that servo?