tires for 98 mustang

[swendall820]

Trying to help my father out with his new toy 98 stang (his mid life crisis)lol
he was wondering what size tires goes on it ? right now it has 17" and speedo is all messed up can some one help us out a little please ?? thank you

 

[apats77]

Well is it a GT? If so it should have 17" with 245/55/17 but it could have come with 225/55/16

Does the car have the stock rear end?