motor screws

Yeah, any 3mm screw from a hobby shop will work. If you go to a hardware store, it is 3mmX.5mm pitch. I pulled the front endbell off of one of my 7XL motors and the endbell was 6mm thick, so get a screw that does not protrude more than 6mm beyond the motor mount. Keep in mind that the depth is different for different brands of motors. To keep it safe, I'd go with 5mm, which is more than enough thread engagement.