there are several MM here that print on reflective. find out what the specs are for this customer, engineer, high intensity, diamond grade, etc...
NOTE: find out if the car was done in grey scale for the gradient.
Nothing worse then printing a graphics and then have them a different color at night because the customer ASSURED you that grey scale was not used
Also find out the type of vinyl used, 3M reflective looks different that Oracal or Avery, etc...