Are there any "rules of thumb" for how much of a motor casing needs to be inside the mmt tube? At least half? All of it? Most of it? I'm scratch-building this Estes Vector Force upscale ... I'll probably fly it mostly on H and I, but I'm thinking I might put a little J in to get L2. The motor casing would protrude above the mmt tube... is that problematic, as long as most of the motor is inside the casing and everything is well-secured?