Your mission, should you accept it, is to make Reagan's Presidency even more successful in the eyes of historians than it already is. Now you might be saying: "But Reagan is already seen as successful!" While that is true, your job is to make Reagan's Presidency from 1981-1989
so successful that he replaces FDR in the top three greatest Presidents among historians. Most historians from what I've seen rank the top three Presidents something like:
1. FDR
2. Abraham Lincoln
3. George Washington
Your mission is to make that ranking:
1. Reagan
2. Lincoln
3. Washington
And......begin!
The problem is FDR's election was a result of the Great Depression, so ideally you'd need the economic slump in the late 70's/early 80's to become a 'Second Great Depression'. How you bring this about I'm not sure.
Failing that, I did start a Thread a few weeks back, based on the Protect and Survive TL, asking what would have happened had the build-up to that Nuclear War occured, but it was stopped at the last minute, just before World War III was due to start. This scenario makes the Cuban Missile Cryses look like a whimper, because the transition to war in Protect and Survive lasts about 6 months and is all very public.
Let's say that in February 1984, Reagan makes a public statement in support of peace. He receives some criticism from right-wing republicans, who would otherwise be in agreement with Reagan's other policies. When a last minute peace agreement is worked out, some even compare him to Neville Chainberlain. However, Reagan's actions receive popular support with the public at large and he takes creddit for salvidging peace, defying many of his foreign policy critics in the 1980 election in the process.
This isn't the end of the matter however, as the economy is now in full-blown ressession as a result of the panic caused by the world situation. Some economists go as far as to say the world is now experiencing a second Great Depression.
On November 6th 1984, Reagan wins a simelarly lopsided election to the one he won IOTL. Despite the economy, he wins bipartisan support as 'The Man Who Stopped The War'. Also, the more critical the world situation, the less coverage news outlets will give to Reagan gafs in the 1984 debates.
Eventually, the economy bounces back quicker than many thought it would. In foreign Polecy, the US and USSR work faster towards disarming, as they have a joint interest in asuring the world doesn't come as close to war ever again. Their efforts are helped by a more unified world in general, again as a result of the near-war cryses of 1983/84.
That's the best way of bringing this about...