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_2020 ( "Fiscal year" real, "2-car sets" real, "4-car sets" real, "6-car sets" real, "8-car sets" real, "Total vehicles" real )

### Question ###
What is the largest 6-car-sets for fiscal year 1968?

### Accurate SQL ###

SELECT MAX("6-car sets") FROM table_2020 WHERE "Fiscal year" = '1968'