CREATE TABLE table_8807 ("Class" CLOB, "Wheel arrangement" CLOB, "Fleet number ( s ) " CLOB, "Manufacturer" CLOB, "Year made" CLOB, "Quantity made" CLOB, "Quantity preserved" CLOB)

What manufacturer made 6 and preserved 1?
SELECT "Manufacturer" FROM table_8807 WHERE "Quantity made" = '6' AND "Quantity preserved" = '1'
SELECT "Manufacturer" FROM "table_8807" WHERE "Quantity made" = '6' AND "Quantity preserved" = '1'