Стабилизатор - тоже в конце 80-x. Башня со стабилизатором пошла на испытания (не в серию) в начале 80-x,
Вот в xронологическом порядке судьба Мардера, точной даты про стабилизатор - нет, но есть даты "до" и "после":
>The Marder IFV was modernized in the early 1980's, chiefly to increase firepower by improving day and night vision devices, surveillance devices and aiming devices as well as the mount of the detachable Milan ATGM, and by strengthening protection against conventional weapons and weapons of mass destruction. The vehicle's weight then increased to 30 tons.
>A design analysis was performed and models of the Marder IFV were manufactured and tested with a 25-mm automatic gun, for which a finned composite shot of increased power was created. A vehicle with the LWT-3 turret stabilized in three planes of laying (armed with a 20-mm automatic gun) also underwent tests. In 1985...