so, just switched over to trinity monster power fuel. I use to use traxxas top fuel. let me say a whole lot different. the trinity runs way more consistent. very impressed. i do need to get a metal prop though. im sick of breaking these damn plastic ones. I am having an issue though with how to take the flex shaft out. it says you have to remove a 1.5 mm set screw. what kind of screw is this a allen key one or a phillips?