Built one 1/144 128mm Flak 40 Zwilling AA Gun on a modified E-100 chassis. Guns fully elevating and rotating. Use this assembly instruction here to assemble the 128mm Flak 40 Zwilling AA without the base and platform:
https://www.combatgroupdynamix.com/Diorama/WargameSeries/Armour/128FlakZwilling/manual/128manualShapeways2021s.jpg
Then assemble the gun onto the E-100 chassis. The four hydraulic anchoring feet can be assembled in lowered (Firing) or raised (travelling) positions.