Remember the descriptions of the chin switches and heads up display? The helmet does not turn, the soldier sees the world in screens in front of his face most of the time. To look out with his own eyes he flips up the visor by tossing his head and then looks around like a deep sea diver in a fish bowl helmet. Think of a big male gorilla's head with the high crest and thick neck. Then cover the face with a curved faceplate that curves well around to the sides so the soldier inside can turn his head and look to the sides. To make it possible to remove a man through the helmet it would have to extend almost from shoulder to shoulder. Pattern the Y rack more like the smoke ejectors common on tanks in the 1950s and 1960s. Think of short launch tubes sticking out of a small package that contains a belt or clip fed machine type gun. An ammo belt or clip is snapped into the mechanism and the weapon programmed to perform. The suit would be all but covered with small latches or clips that equipment could be quickly snapped into or on to.