According to www . fuel economy . gov ( no spaces ) For a 1989 Lincoln Town Car ( 15 city / 22 highway miles per U.S. gallon )
The 1989 Honda Accord gets 21 miles per gallon in the city. It gets 27 miles per gallon on the highway. It has a combined rating of 23 miles per gallon.
1 billion miles to the gallon
I am getting close to 10 - 11 miles to the gallon in a 1989 ford dually with a 460 fuel injected engine.
18 mpg city
about 7-13 mpg
anywhere from 20 to 28. Depends how you drive.
According to my Chilton's Auto Repair Manual : A 1989 Lincoln Town Car has a ( 20.0 U.S. gallon fuel tank )
You will be lucky to get around 15 mpg.
Depends on which engine/transmission it has installed which you failed to list.
gallon of gas in 1989 was about $1.02
there is a special tool that you use to put it on, your local checker or auto store should have one.