Ok, here's what changed:
-the Top "bar" on the cockpit was removed, now it's just a solid angled pane of glass that meets at the top - realistically this would allow better aiming and vision for the pilot.
-Cockpit was scaled down so that the rest of the ship could be increased slightly in size, otherwise it'd have been too big for a light fighter and too small for a VHF.
-The bottom two glass panels on the cockpit were changed to solid steel.