Modernizing HMS Vanguard with 1980s technology

How could a mothballed HMS Vanguard be modernized in 1990 using only systems active between 1980 and 1990?

Proposals include new secondary guns and superstructure, Sea Wolf, and an aft aviation deck, but the hull needs major rebuilding and some panel suggestions exceed the stipulated in-service equipment.

The counterfactual assumes Vanguard survives in mothballs until 1990 and allows unlimited spending on equipment in service during 1980-1990. Suggestions include replacing the superstructure and 5.25-inch secondary armament, fitting 76 mm guns and Sea Wolf, and removing the aft 15-inch turrets for helicopters. A deck over retained turrets raises weight and gun-blast problems for aircraft and their maintainers. By 1990 the hull would itself require extensive reconstruction, so an unlimited budget does not make this a modest refit. Fox then proposes a more extravagant Harrier-carrying conversion with forward heavy guns and Mark 41 cells. That proposal includes recollections of unbuilt weapons, explicitly qualified as uncertain, and therefore stretches the question's in-service equipment restriction.