Table schema:
CREATE TABLE table_name_47 (year INTEGER, laps VARCHAR, co_driver VARCHAR, position VARCHAR)

Question: What is the lowest Year, when Co-Driver is Warren Luff, when Position is 7th, and when Laps is less than 161?
SQL: SELECT MIN(year) FROM table_name_47 WHERE co_driver = "warren luff" AND position = "7th" AND laps < 161