One of the reasons that Nixon's Southern strategy was possible was because the Democrats had thrown away their supremacy over Civil Rights. Unless there's some equivalent issue that's toxified Labour, I don't see it really working. Nor, for that matter, does it need to. As 2015 proved, the Tories have enough support in the rural and suburban north to deliver an overall majority.
But if it was going to, then I'd suggest something like a combination of a far-left Labour leader combined with a Tory who played the patriot card to the white working class.
So Tony Benn vs Airey Neave?
Though more seriously and on your first point, there were elements of this in 1979, in which the Conservatives targeted the Working Class who felt burnt by Labour and the Winter of Discontent. Looking at a map, of the 50 lost seats you can a noticeable loss in the Hull-Mersey belt, the Thames Estuary, and in a fair few of the Collieries Constituencies. This could be a bigger switch of seats without the lingering memories of the 3 Day Week and the strikes under Heath, and if the Tories drove up to the hilt for these votes. As fjihr just suggested as I was writing, Labour winning in 1970 could help the Conservatives a lot. Heath is replaced by someone more competent. Labour implements
In Place of Strife and various other legislation, and Wilson steps down in 1972, replaced by either Jenkins, Callaghan, or Castle, with strife between the Party and Trade Unions over the implementation of the White Paper. The 1974/1975 Election will be crucial to this realignment- the Tories pursue a 'Northern Strategy' to gobble up seats burnt by Labour, with the Liberals benefiting by this move and further helping to erode Labour in certain areas, be it as simple as splitting votes. Labour will undoubtedly be wounded by this and loose the election, especially if the Tories get a foot in the Hull-Mersey belt; after this point, Labour lurches to the right with Callaghan or Jenkins or further left under Foot or Shore, none of which will really encourage the traditional base.
Whoever is the Conservative Leader from 1970-197x is crucial; this person has to recognize the gap being formed by Labour between them and the Unions and industrial worker force, and exploit this, and keep exploiting it with their successor.
I do remember back in 2014 how there was this sense of a re-alignment, in Cameron, by pursuing Osborne's Northern Powerhouse, was transforming the Conservatives into the Party of the Workers, whilst Labour began to shift towards business.