CREATE TABLE table_67583 ("Model" TEXT, "Specification" TEXT, "Build date" TEXT, "Total produced" FLOAT, "Wheel arrangement" TEXT, "Prime mover" TEXT, "Power output" TEXT)

What is the build date of the locomotives with a total produced less than 45 and a fb-2 model?
SELECT "Build date" FROM table_67583 WHERE "Total produced" < '45' AND "Model" = 'fb-2'
SELECT "Build date" FROM "table_67583" WHERE "Model" = 'fb-2' AND "Total produced" < '45'