The 1975 models were introduced in September 19, 1974. That is why it can have a production date of 1974. If you look at the VIN number, the 6th digit represents the model year. So it should be a "5".
The series designation for the sedan was : F23. The limo was F33.
The series 75 limousines had the electric division window. The series 75 sedans did not. Most people called them Limousines however as they shared the same 9-passenger long wheelbase.
The Limos had a black leather front seat and black front interior trim. While the rear compartment was cloth and was available in black Moselle cloth or Medium Graystone Potomac cloth. The D'Elegance option was available but only with Blue Medici velour. The series 75 sedans had the same front color and material to match the rear compartment.
A formal Landau roof was optional. This included a padded vinyl top, deleted rear quarter windows, reduced rear window and landau bows on the rear quarters. The landau bows and/or reduced rear window size could be omitted however.
Opera lamps were available at extra cost.
The ACRS airbag option was not available on the series 75 cars. The Limousine was not available with the 6-way power seat or dual comfort seat option due to the center partion.