Question: When was the motor gear of the LMS 1946 no. 1901 model fitted?
Schema: create table table_2030453_1 (date_motor_gear_fitted varchar, lms_1946_no varchar, PRIMARY KEY (date_motor_gear_fitted))
SQL: select date_motor_gear_fitted from table_2030453_1 where lms_1946_no = 1901