Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_40791 ( "Date" text, "Tournament" text, "Winning score" text, "Margin of victory" text, "Runner(s)-up" text )

### Question ###
On what date was the tournament played that eneded with a winning score of +6 (74-71-70-71=286) and margin of victory of 2 strokes, and with Arnold palmer as the runner-up?

### Accurate SQL ###

SELECT "Date" FROM table_40791 WHERE "Runner(s)-up" = 'arnold palmer' AND "Margin of victory" = '2 strokes' AND "Winning score" = '+6 (74-71-70-71=286)'