What would a Thatcher Premiership look like in a TL without a President Reagan? My leading questions here are, to what degree did the Tories fortunes and policies in the 1980's stem from a close relationship with Washington, and to what degree was this strength derived from having an ideologically close friend in the White House?
Here's a rough TL to imagine this question in:
1975 -- Thatcher beats Heath for the Conservative Leadership (as OTL)
1976 -- Ford defeats Carter, and is (re)elected
1979 -- The Conservatives win a majority in Parliament; Thatcher becomes PM (as OTL)
1980 -- Jerry Brown wins the US Presidency