Some clarifications on how the M-Drive works in my version of Mongoose Traveller.

An M-Drive is mounted at the rear of a ship, and most of the thrust is directed in that direction, pushing the craft forward. Up to 25% of the ship's thrust can be redirected in other directions. This doesn't require special thrusters - it is a feature of the magic M-Drive.

The thruster plates glow a bright bluish white when in use, giving off light, noise and heat. The amount is proportional to their size and power.