Complex sentence: Deathstalker 1 is the colloquial name of a M551 Sheridan tank that was used during the Vietnam War (2nd Indochina War) and is now in one of the worlds largest privately owned tank collections.
Split into simpler sentences: Deathstalker 1 is the colloquial name of a M551 Sheridan tank that was used during the Vietnam War. It is now in one of the world's largest privately owned tank collections.