Kirov as the political case for retaining Vanguard

How could supporters prevent a retained HMS Vanguard from being scrapped during the 1970s?

Keep her until Kirov is laid down in 1974, then use the new Soviet battlecruiser as the Cold War political case for retaining and upgrading Vanguard.

The hardest period for preserving Vanguard would be the years before a new Soviet capital ship offered an obvious comparison. Kirov's laying down in 1974 would let supporters recast the British battleship as an answer to a Soviet battlecruiser. That claim would be politically powerful even if the ships differed greatly in design and role. Size, visual presence, and status are central to the argument: the Royal Navy would be answering the public symbol of a Soviet capital ship as much as its precise weapons. A battleship's cultural presence could therefore carry procurement weight beyond a narrow calculation of tactical utility. Once the comparison took hold, Vanguard would have a better chance of receiving modernisation rather than being treated only as an expensive survivor of an earlier era.