It's actually a Crown Vic LTD but it's hard to tell from the front, they only made a handful of LTD and Grand Marquis coupes from 1979 through 1987 with 87' being the final production year.
Production numbers comparison for 1986 is like 6,500 LTD coupes to 110,000 4 doors. Last year 87' there were only around 5,600 LTD coupe made.