The Falklands war saved Thatcher's rear-end big time. Prior to the war, the SDP-LP Alliance polled above 50%.
What if the Falklands War were avoided (Maggie never cuts back on the security in the islands) and the Alliance won an overwhelming victory?
I imagine there'd still be a shift towards economic liberalization, but without the issues of Thatcher's personality they might settle a bit better.
Jenkins was the designated Prime Minister, so I assume it goes to him.
Could a successful Alliance have gotten the Wets to coalesce with them?