Actually your wrong, the neuro helmets are just use for balanced when combined with the battlemech's gyro. (Some more advance Nuero helmet allow some controls to be thought activated but not to control a whole battlemech.)
A battlemech is controlled by a joystick(s), peddles, and a speed adjuster. There are switches that change the joystick's controls so it manipulates the arms instead of aiming so you can punch/grab thing. But not up to the function where it is your second body.